Entries |
Document | Title | Date |
20080211416 | ILLUMINATION DEVICES USING EXTERNALLY INTERCONNECTED ARRAYS OF LIGHT EMITTING DEVICES, AND METHODS OF FABRICATING SAME - A light emitter, comprising light emitting devices mechanically interconnected by a common substrate and an interconnection submount. The light emitting devices are electrically interconnected by the submount to provide an array of serially connected subsets of light emitting devices, each subset comprising at least three light emitting devices electrically connected in parallel. Also, a light emitter comprising first light emitting devices mechanically interconnected by a first common substrate, and second light emitting devices mechanically interconnected by a second common substrate, the first light emitting devices being mechanically and electrically connected to the second light emitting devices. Also, a light emitter comprising mechanically interconnected light emitting devices and means for mechanically and electrically interconnecting the plurality of light emitting devices to provide an array of serially connected subsets of light emitting devices, each subset comprising at least three light emitting devices electrically connected in parallel. Also, methods of fabricating light emitters. | 09-04-2008 |
20080315777 | Variable-Effect Lighting System - A variable-effect lighting system includes a lamp assembly and a lamp controller coupled to the lamp assembly. The lamp assembly comprises a number of multi-coloured lamps in series with an AC voltage source and in series with each other. Each multi-coloured lamp comprises a first illuminating element for producing a first colour of light, and a second illuminating element for producing a second colour of light. The lamp controller is configured to vary the colour produced by the lamps by varying the conduction interval of each illuminating element according to a predetermined pattern. The controller is also configured to terminate the variation upon activation of a user-operable input to the controller. | 12-25-2008 |
20080315778 | LIGHT-EMITTING-DIODE DRIVE CIRCUIT - A light-emitting-diode drive circuit for driving n (where n is a natural number equal to or greater than two) light-emitting diodes (LED | 12-25-2008 |
20090058312 | ENERGY EFFICIENT FLUORESCENT LAMP - To decrease a power consumption of a fluorescent lamp, the fluorescent lamp is provided with a high efficiency fluorescent coating, generating more light upon receipt of a conventional amount of radiation. Decreasing the power supplied to the lamp decreases the radiation supplied to the fluorescent coating and thus the light output of the lamp. Due to the increased light output of the fluorescent coating, the light output level of the fluorescent lamp may be kept substantially equal to a light output level of a conventional lamp. | 03-05-2009 |
20090085489 | CIRCUIT AND METHOD FOR DRIVING AND CONTROLING LIGHT SOURCE - A light source driving circuit including a driving module, a plurality of first switches, a detecting unit, and a control unit is provided. The plurality of first switches is respectively coupled to corresponding light sources and these light sources are driven by the driving module. The detecting unit is coupled to the driving module to detect a working parameter of each light source and transmit the working parameter to the control unit. When the detecting unit detects some of these light sources are broken down, the control unit sequentially turns on the first switches to find out the failed light source. Moreover, the first switch coupled to the failed light source is remained on, and the driving signal is regulated according to the number of the failed light source, such that the brightness of the panel does not decrease. | 04-02-2009 |
20090195169 | POWER SUPPLY CIRCUIT WITH CURRENT SHARING FOR DRIVING MULTIPLE SETS OF DC LOADS - The present invention provides a power supply circuit for driving multiple sets of DC loads. The power supply circuit includes a current providing circuit, a sharing circuit and a current control unit. The current providing circuit receives and regulates a supply voltage into specified output currents to be supplied to the multiple sets of DC loads. The sharing circuit is connected in series with output terminals of the current providing circuit and the multiple sets of DC loads. The sharing circuit includes at least one coupling inductor member for performing equal current sharing among the multiple sets of DC loads. The current control unit is connected to the current providing circuit and the multiple sets of DC loads for detecting magnitudes of the current passing through the multiple sets of DC loads and controlling the output currents from the current providing circuit. | 08-06-2009 |
20090273290 | Boost LED Driver Not Using Output Capacitor and Blocking Diode - An LED driver is disclosed that boosts an input voltage to drive any number of LEDs in series. The driver includes a switch-mode current regulator that supplies regulated current pulses to the LEDs. No high voltage output capacitor is used to smooth the current pulses, so the LEDs are turned on any off at the switching frequency. Also, no blocking diode between the switching transistor and the LEDs is used. The cathode of the “bottom” LED in the string is connected to ground via a current sense resistor. In parallel with the sense resistor is connected an RC filter using a small, low voltage filter capacitor. The RC filter provides a substantially smooth feedback voltage for the current regulator to control the duty cycle of the switching transistor so that the feedback voltage matches a reference voltage. | 11-05-2009 |
20090302771 | SERIES-TYPE LED LAMP STRIP MODULE - A series-type LED lamp strip module includes a first LED lamp strip module and a second LED lamp strip module. The first LED lamp strip module and the second LED lamp strip module both include a power switch controller, at lease one LED lamp strip, a signal output adaptor, a signal input adaptor, a power plug, and a power socket. The power plug of the second LED lamp strip module is inserted into the power socket of the first LED lamp strip module, and the signal output adaptor of the first LED lamp strip module is electrically connected to the signal input adaptor of the second LED lamp strip module so as to connect the first LED lamp strip module and the second LED lamp strip module. In addition, a microcontroller unit outputs a control signal to lighten light emitting diodes in different types to produce multiple brightness variations. | 12-10-2009 |
20100123403 | ELECTRONIC CONTROL TO REGULATE POWER FOR SOLID-STATE LIGHTING AND METHODS THEREOF - Apparatus and methods to regulate an input power applied to a plurality of light emitters are provided. A regulator device includes a plurality of switches and a control circuit that controls the plurality of switches. The plurality of switches selectively couple respective strings of the light emitters in series to the input power to emit light when deactivated. The control circuit may deactivate a number of the switches to couple the respective light emitters to the input power in response to a sensed operational parameter of the input power. The control circuit may adjust the number of the switches deactivated in response to a change in the sensed operational parameter of the input power. A number of the light emitters may be coupled to the input power regardless of the sensed operational parameter of the input power. | 05-20-2010 |
20100127629 | LIGHT EMITTING DEVICE - A light emitting device is disclosed herein. An embodiment of the light emitting device comprises a first plurality of light emitters comprising a first group and a second group, wherein the first group is connectable in series to the second group. A first driver is connected to the first group. A second driver is connectable to the second group. A first voltage comparator is coupled to the first driver, wherein the voltage comparator compares the voltage of the first driver to a predetermined voltage. The light emitting device is in a first state when the voltage of the first driver is below the predetermined voltage. The light emitting device is in a second state when the voltage of the first driver is greater than the predetermined voltage. The light emitting device is in the first state, the first group is connected in series with the second group to form a series circuit between the first driver and a reference voltage. When the light emitting device is in the second state, the first group is connected between the first driver and the reference voltage and the second group is connected between the second driver and the reference voltage. | 05-27-2010 |
20100148681 | DRIVING CIRCUIT WITH CONTINUOUS DIMMING FUNCTION FOR DRIVING LIGHT SOURCES - A driving circuit for controlling power of a light source includes a power converter coupled to a power source and the light source, and a dimming controller coupled to the power converter. The power converter can receive power from the power source and provide a regulated power to the light source. The power converter includes a control switch coupled in series with the light source. The dimming controller can monitor a power switch coupled between the power source and the driving circuit, and receive a dimming request signal and a dimming termination signal. The dimming request signal can indicate a first set of operations of the power switch. The dimming termination signal can indicate a second set of operations of the power switch. The dimming controller can continuously adjust the regulated power from the power converter by controlling the control switch if the dimming request signal is received, and can stop adjusting the regulated power from the power converter if the dimming termination signal is received. | 06-17-2010 |
20100171431 | VISIBLE INDICATION OF MISTAKEN LAMP USE - A lamp includes an arc tube and a lighting unit for lighting the arc tube. The lighting unit includes a rectifier circuit, a smoothing circuit for partial smoothing, and an inverter circuit having a pair of switching elements. The smoothing circuit smoothes portions of the output voltage of the rectifier circuit below the first voltage value and outputs a voltage that falls between the first voltage value and the second voltage value. The discharge sustaining voltage of the arc tube is set to fall between the first and second values of the voltage Vdc output from the smoothing circuit. | 07-08-2010 |
20100295460 | LIGHT EMITTING DIODE CIRCUIT - A light emitting diode (LED) circuit is provided. A light emitting diode (LED) circuit includes an alternating current (AC) source, a rectifier, a voltage-limiting circuit, and an LED module. The AC source provides an AC voltage, and the rectifier generates a first rectified voltage according to the AC voltage. An upper limit of the first rectified voltage is substantially restricted at a rated voltage by the voltage-limiting circuit, and the voltage-limiting circuit generates a second rectified voltage according to the first rectified voltage, in which the second rectified voltage is lower than the rated voltage. The LED module receives the second rectified voltage. Thereby, when the AC voltage is unstable, fluctuation of current flowing through the LED module can be substantially reduced. | 11-25-2010 |
20100301762 | LED DRIVING CIRCUIT AND BACKLIGHT MODULE - A LED driving circuit and a backlight module using the same are disclosed. The LED driving circuit comprises a LED module and a current controlling unit. The LED module has a plurality of the LED strings, each having a driving terminal. The current controlling unit has a plurality of current balancing terminal coupled to the driving terminal, for balancing the currents flowing through the LED strings. The current controlling unit receives a mode switch signal, controls the amount of the currents of the LED strings about a first current value when the mode switch signal represent a first mode, and controls the amount of the currents of the LED strings about a second current value when the mode switch signal represent a second mode. | 12-02-2010 |
20100308739 | Apparatus, Method and System for Providing AC Line Power to Lighting Devices - An apparatus, method and system are disclosed for providing AC line power to lighting devices such as light emitting diodes (“LEDs”). An exemplary apparatus comprises: a plurality of LEDs coupled in series to form a first plurality of segments of LEDs; a plurality of switches coupled to the plurality of segments of LEDs to switch a selected segment into or out of a series LED current path in response to a control signal; a memory; and a controller which, in response to a first parameter and during a first part of an AC voltage interval, determines and stores in the memory a value of a second parameter and generates a first control signal to switch a corresponding segment of LEDs into the series LED current path; and during a second part of the AC voltage interval, when a current value of the second parameter is substantially equal to the stored value, generates a second control signal to switch a corresponding segment of LEDs out of the first series LED current path. | 12-09-2010 |
20110080101 | ELECTRONIC DEVICE - An electronic device is provided. The electronic device includes a plurality of load units, a plurality of serial-parallel switch units and a control module. The control module switches the serial-parallel switch units to a first state or a second state according to a level variation of an input voltage. Connection relations of the load units are correspondingly changed according to the level variation of the input voltage. In this way, the electronic device can be driven by an alternating-current voltage. | 04-07-2011 |
20110089844 | CONTINUOUS STEP DRIVER - A light emitting diode (LED) lamp includes an LED cluster including LED groups arranged in series, a power source configured to provide an input power to the LED cluster, and a driving unit configured to adjust a number of the LED groups connected to a current path of the LED cluster in series based on the input power to the LED cluster. | 04-21-2011 |
20110115390 | LED LAMP - An exemplary light emitting diode (LED) lamp includes a lamp body, an LED module and a switching member. The LED module is mounted on the lamp body and includes a plurality of first LED components emitting a first light with a first color temperature and a plurality of second LED components emitting a second light with a second color temperature. The switching member is mounted around the lamp body and can be operated to cause the LED lamp to work in different modes. In the different modes, different numbers of the first and second LED components are driven to emit light with different color temperatures. | 05-19-2011 |
20110121741 | PLANAR ILLUMINATING DEVICE AND DISPLAY DEVICE PROVIDED WITH SAME - In a backlight device that adjusts brightness by turning on/off switches provided in parallel to respective LEDs, deterioration and breakage of the LEDs, variability in brightness, and flickering are suppressed. In at least one embodiment, a backlight device includes: an LED array including a plurality of LEDs connected in series and bypass switches (transistors) provided in parallel to the respective LEDs; a bypass switch control circuit for switching between an on state and an off state of the bypass switches; an FET having a drain terminal connected to the LED array and a source terminal grounded; a constant current drive control circuit for applying a constant current to the LED array by applying a predetermined voltage to a gate terminal of the FET; and a capacitor whose one end is connected to the gate terminal of the FET and whose other end is grounded. | 05-26-2011 |
20110127923 | LED DRIVER AND DRIVING METHOD - An LED driver includes a power converter to convert an input voltage to a regulated voltage, a current source to be connected with an LED string in series between the power converter and a bias node, and a switching circuit to apply a bias voltage to the bias node to set the total voltage drop of the LED string and the current source. By controlling the total voltage drop of the LED string and the current source, the LED driver will automatically select a boost mode or a buck mode for operation, thereby improving the efficiency thereof. | 06-02-2011 |
20110133659 | Power Source Control Method for a Multi-module LED Circuit and Related Control Device and LED Circuit - A power source control method for a multi-module light-emitting diode (LED) circuit includes detecting a signal characteristics value according to a plurality of switching signals, being used for controlling the conduction of currents in the plurality of lighting modules, comparing the signal characteristics value with a pre-determined value to generate a comparing result, and outputting the comparing result to an external power supply device, such that the external power supply device can adjust the voltage level of an input voltage of the multi-module LED circuit according to the comparing result. | 06-09-2011 |
20110133660 | LIGHT EMITTING DEVICE, LIGHTING DEVICE, LIGHTING SYSTEM, LIGHT EMITTING DIODE CIRCUIT, MOUNTING SUBSTRATE, AND LIGHT EMITTING METHOD FOR LIGHT EMITTING DIODE - A lighting system includes: plural light emitting chips ( | 06-09-2011 |
20110140618 | LIGHT EMITTING DEVICE - A light emitting device including a voltage source, a light emitting unit, and a current source is provided. The voltage source is coupled to the light emitting unit for supplying a voltage. The light emitting unit includes n light emitting diodes (LEDs) and n current control switches, wherein n is greater than or equal to 3. The LEDs are respectively coupled to the current control switches in series. The current control switches are turned on and off according to a current threshold. The current source is coupled to the light emitting unit for supplying a fixed current. Thereby, the luminous intensity of the light emitting device remains stable even when some of the LEDs fail. | 06-16-2011 |
20110140619 | DIFFERENTIAL DRIVING CIRCUIT FOR POWERING A LIGHT SOURCE - A differential driving circuit for powering a light source is disclosed. The differential driving circuit includes a first set of switches and a second set of switches. A first current from a power source flows through the first set of switches to charge a first energy storage element when the first set of switches are turned on. A second current from the first energy storage element flows through the second set of switches to power the light source when the second set of switches are turned on. The differential driving circuit further includes a second energy storage element coupled to the light source in parallel and for providing a differential voltage to the light source. | 06-16-2011 |
20110175537 | AC LED LAMP - An alternating current (AC) light-emitting diode (LED) lamp includes a first AC power end, a second AC power end, a lighting module and a direct current (DC) power output circuit. The lighting module has a first end, a second end and at least one LED unit, wherein the first end is electrically coupled to the first AC power end. The at least one LED unit has one or more LEDs connected in series. The DC power output circuit has a first end and a second end, wherein the second end of the DC power output circuit is electrically coupled to the second AC power end, while the first end of the DC power output circuit is electrically coupled to the second end of the lighting module. The DC power output circuit has a DC output side. | 07-21-2011 |
20110199011 | LIGHT-EMITTING DIODE DRIVING CIRCUIT AND PLANAR ILLUMINATING DEVICE HAVING SAME - There is provided an LED driver capable of preventing deterioration of display quality for moving image display in a display device employing, as a backlight, light-emitting diodes formed in a plurality of rows. An LED driver includes a plurality of bypass switches connected in parallel with a respective plurality of light-emitting diodes; switch control circuits that control on and off states of the bypass switches; registers provided in one-to-one correspondence with the bypass switches; a first counter and a second counter that count clocks; and comparators that compare the value of the first counter or the second counter with the values of the registers. Here, as timing control signals, a first reset signal is provided to the first counter and a second reset signal is provided to the second counter. | 08-18-2011 |
20110204802 | LED ASSEMBLY DRIVING CIRCUIT - A circuit for driving a LED assembly comprises at least one LED illumination device. The circuit comprises:—a switch,—an inductor, in a series connection with the switch, the switch to in a closed state thereof charge the inductor and in an open state thereof allow the inductor to discharge,—a current measurement element to measure a current flowing through at least one of the inductor and the LED illumination device in the open and closed state of the switch. The switch, inductor and current measurement element are arranged to establish in operation a series connection with the LED illumination device. The circuit further comprises a comparator to compare a signal representing the current measured by the current measurement element with a reference. An output of the comparator is provided to a driving input of the switch for driving the switch from one of an open and a closed state of the switch to the other one of the open and the closed state of the switch upon a change of an output state of the output of the comparator. | 08-25-2011 |
20110273102 | AC DRIVEN SOLID STATE LIGHTING APPARATUS WITH LED STRING INCLUDING SWITCHED SEGMENTS - A diode selection circuit for a light emitting apparatus according to some embodiments includes a plurality of light emitting devices coupled in series. The diode selection circuit includes a comparator configured to receive a rectified AC input signal and a reference voltage and to generate a control signal in response to comparison of the rectified AC input signal with the reference voltage, a voltage controlled current source configured to supply a current to the plurality of light emitting diodes that is proportional to the rectified AC input signal, and a switch configured to receive the control signal and to shunt current away from at least one of the plurality of light emitting devices in response to the control signal. | 11-10-2011 |
20110273103 | LED LAMP WITH ADJUSTABLE ILLUMINATION INTENSITY BASED ON AC VOLTAGE AMPLITUDE - An LED lamp with adjustable illumination intensity is disclosed. The LED lamp comprises an illumination block having first, second, and third illumination modules, and first and second switches. The first, second, and third illumination modules are coupled in series between a rectification voltage node and a third connection node. The first switch selectively connects a first connection node shared by the first and second illumination modules to a basis voltage node. The second switch selectively connects a second connection node shared by the second and third illumination modules to the basis voltage node. The third connection node is coupled to the basis voltage node. A control block provides the first and second control signals respectively controlling the first and second switches, wherein the logic states of the first and second control signals are based on the amplitude of a driving voltage measured between the rectification and basis voltage nodes. | 11-10-2011 |
20110285300 | Constant-Current Controller for LED Light String - A constant-current controller for a LED light string has a control unit, multiple constant current circuits, multiple first switches and multiple second switches. The control unit outputs driving signals to turn on the first switches, causing the second switches being turned on subsequently. Therefore, the constant current circuits output electric currents flowing through the second switches to activate the LED light string. | 11-24-2011 |
20120001558 | TRANSISTOR LADDER NETWORK FOR DRIVING A LIGHT EMITTING DIODE SERIES STRING - Ladder network circuits for controlling operation of a string of light emitting diodes (LEDS). The circuits include a number of sections connected in series. Each section includes one or more LED junctions, a variable resistive element coupled to the LED section, and a switch coupled to the variable resistive element and the LED section for controlling activation of the LED. The sections can include a transistor coupled between the switch and variable resistive element. The series of sections are connected to an AC power source, rectifier, and dimmer circuit. When receiving power from the power source, the sections activate the LEDs in sequence throughout the series of the sections. The dimmer circuit controls activation of a selection of one or more of the sections in order to activate in sequence the LEDs in only the selected sections, providing for both dimming and color control of the LEDs. | 01-05-2012 |
20120038285 | LED SWITCH CIRCUITRY FOR VARYING INPUT VOLTAGE SOURCE - An LED array switching apparatus, comprises: a plurality of LED segments D | 02-16-2012 |
20120062132 | Regulated Voltage Protection Circuit, Display Controller and LED Driving Method of the Same - A regulated voltage protection circuit includes a bias-voltage generating circuit and a clamping circuit. The bias-voltage generating circuit provides a bias-voltage. The clamping circuit is coupled to a plurality of light-emitting diode (LED) strings and a driving circuit, and generates a plurality of clamped voltages that are respectively transmitted to a plurality of input pads of the driving circuit according to the bias-voltage. The regulation voltage protection circuit protects against electrical overstress (EOS) by protecting the driving circuit during low-voltage fabrication process chip manufacturing. | 03-15-2012 |
20120081017 | LED STRING DRIVER WITH POWER FACTOR CORRECTOR AND CURRENT GOVERNOR - A solid state lighting controller arranged for use with a single stage power factor correction switched mode power supply, a light emitting diode (LED) string and a current sense element arranged to sense current through the LED string, the solid state lighting controller constituted of: a current governor in series with the LED string exhibiting a governor differential amplifier and a governor electronically controlled switch responsive to the output of the governor differential amplifier, the current governor arranged to limit current flow through the LED string responsive to a current limit reference; and a feedback circuit exhibiting an error amplifier, the feedback circuit arranged to feedback a signal to the power factor correction switched mode power supply controller whose value is a function of the difference between the current through the LED string sensed by the current sense element and a target current signal. | 04-05-2012 |
20120098444 | DRIVING APPARATUS FOR LIGHT-EMITTING DIODE CURTAIN LAMP - A driving apparatus for light-emitting diode curtain lamp is applied to a direct current power source and at least a light-emitting diode light string. The driving apparatus for light-emitting diode curtain lamp includes a master control unit, at least a slave control unit, and a transmission line. The master control unit is electrically connected to the direct current power source. The slave control unit is electrically connected to the master control unit and the light-emitting diode light string. The transmission line is electrically connected to the master control unit and the slave control unit. The slave control unit is controlled by the master control unit to drive the light-emitting diode light string. The transmission line is used to transit control signals and synchronous signals. | 04-26-2012 |
20120098445 | LIGHTING SYSTEM AND METHOD FOR CONTROLLING THE SAME - A lighting system which automatically assigns a unique address to each lighting device and controls each lighting device assigned the unique address is disclosed. The lighting system may include a plurality of lighting apparatuses, at least one bridge coupled to the plurality of lighting apparatuses, and a lighting controller coupled to the at least one bridge for controlling the lighting apparatuses. One of the at least one bridge or the controller may generate address data for assigning an address to one of the plurality of lighting apparatuses. The plurality of lighting apparatuses may include an LED module, a connection circuit configured to control a connection between the at least one bridge and the plurality of lighting apparatuses, and a controller configured to control the connection circuit based on the address. | 04-26-2012 |
20120098446 | LIGHTING SYSTEM AND METHOD FOR CONTROLLING THE SAME - A lighting system automatically assigns a unique address to each lighting apparatus, and controls each lighting apparatus based on the assigned address. The lighting system may include a first lighting apparatus, a second lighting apparatus connected to the first lighting apparatus in series, and a bridge device coupled to the first and second lighting apparatuses in series and configured to assign an address to the first and second lighting apparatuses. The bridge device may transmit a first data packet to initialize the lighting apparatuses for address assignment, and a control circuit may disconnect the connections between the lighting apparatuses during address assignment. | 04-26-2012 |
20120139430 | LED DRIVER CIRCUIT AND LED DRIVER SYSTEM - A withstand voltage of the LED driver circuit is set to be lower than an LED power supply voltage of the power supply and be higher than a first voltage value obtained by subtracting a voltage drop across whole of the LEDs connected in series caused by the second constant current from the LED power supply voltage. | 06-07-2012 |
20120146523 | LIGHT EMITTING DIODE DRIVER - A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes a string of LEDs divided into n groups and the n groups of LEDs is electrically connected to each other in series, where a downstream end of group m-1 is electrically connected to the upstream end of group m. The driver circuit also includes a power source coupled to an upstream end of group | 06-14-2012 |
20120146524 | LIGHT EMITTING DIODE DRIVER HAVING PHASE CONTROL MECHANISM - A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes a string of LEDs divided into n groups, the n groups of LEDs being electrically connected to each other in series, a downstream end of group m−1 being electrically connected to the upstream end of group m. The driver circuit also includes a power source coupled to an upstream end of group | 06-14-2012 |
20120153853 | BACKLIGHT UNIT - A backlight unit includes a driving circuit outputting a driving voltage, light source strings, a first feedback circuit, a first current control circuit, a second feedback circuit, and a second current control circuit. Each light source string includes light sources and receives the driving voltage to generate light. The first feedback circuit outputs a first control signal based on a measured current at input terminals of the light source strings. The first current control circuit receives the driving voltage and controls a strength of the current input at the input terminals based on the first control signal. The second feedback circuit outputs a second control signal based on a measured current at each output terminal of the light source strings. The second current control circuit controls a strength of a current output at each output terminal of the light source strings. | 06-21-2012 |
20120176052 | Light-Emitting Diode Drive Control Circuit - The present invention provides a light-emitting diode (LED) drive control circuit having an input terminal and an output terminal. The input terminal and a switching device are coupled in series between power supply terminals. The output terminal is coupled to an LED. The switching device includes a single-pole double-throw switch. A first branch of the single-pole double-throw switch is a wire. A second branch of the single-pole double-throw switch includes a resistor and an indicator in series. The circuit includes a semiconductor switch that is either on or off. When the single-pole double-throw switch is switched to the first branch, the semiconductor switch is on and turns on the LED. When the single-pole double-throw switch is switched to the second branch, the semiconductor switch is off and turns off the LED. The circuit can effectively turn the LED on and off to avoid power leakage and slight emission of light. | 07-12-2012 |
20120194088 | HIGH BRIGHTNESS LED DRIVING CIRCUIT - A high brightness LED driving circuit has a rectifying unit, an LED string, multiple electric switches, a current detection unit and a current adjusting unit. The current adjusting unit turns on and off the electric switches to form a corresponding order current loop. The LED string has multiple LED units. The order of the current loop indicates the number of the LED units being activated. The LED units in each order current loop has the LED units in the previous lower order current loops. In the cycle of voltage-rising period and the voltage-dropping period, the current adjusting unit turns on one electric switch to respectively form a higher and a lower order current loop. Therefore, the brightness of the LED string should be uniform. | 08-02-2012 |
20120212144 | ILLUMINATION DEVICE - An illumination device includes a light emitting unit; and a lighting circuit, to which the light emitting unit is installed, for supplying an output voltage to the light emitting unit. The light emitting unit includes a light emitting element which is connected to an output terminal of the lighting circuit and emits light by the output voltage supplied from the lighting circuit; and a current limiting unit which limits a current flowing into the light emitting element portion from the lighting circuit at the time when the light emitting unit is installed to the lighting circuit. | 08-23-2012 |
20120217887 | LED LIGHTING SYSTEMS, LED CONTROLLERS AND LED CONTROL METHODS FOR A STRING OF LEDS - LED controllers, LED lighting systems and control methods capable of providing an average luminance intensity independent from the variation of an AC voltage. LEDs are divided into LED groups electrically connected in series between a power source and a ground. A disclosed LED controller has path switches, a management center and a line waveform sensor. Each path switch is for coupling a corresponding LED group to the ground. The management center controls the path switches. When turning off an upstream path switch, the management center controls a downstream path switch for a downstream LED group to make the driving current passing the upstream LED group substantially approach a target value. The line waveform sensor is coupled to the power source, sensing the waveform of the input voltage of the power source. The line waveform sensor is configured to decrease the target value when the input voltage increases. | 08-30-2012 |
20120229039 | BACKLIGHT UNIT HAVING LIGHT EMITTING DIODE - A backlight unit has a Light Emitting Diode (LED). The backlight unit includes a base member, and a light source unit provided on the base member and including p light source blocks, where p is a natural number equal to or greater than 2. The light source blocks are sequentially arranged to emit light, and each of the light source blocks includes at least one LED package. The LED package includes an LED configured to generate light in response to a driving voltage applied from the outside. A main lead is connected to the LED and configured to apply the driving voltage to the LED. At least one sub lead is separated from the main lead and configured to provide the driving voltage to an adjacent light source block. | 09-13-2012 |
20120248998 | LED DRIVER AND LED ILLUMINATOR HAVING THE SAME - An LED driver includes a power converter that includes a transformer having primary and secondary windings and a switching element connected to the primary winding and supplies power through the primary winding to an LED load, a feedback unit that is connected to the secondary winding and includes a control information detector to detect control information related to ON/OFF control of the switching element and a voltage detector to detect winding voltage information related to a voltage of the secondary winding, and a controller that carries out the ON/OFF control of the switching element. The feedback unit generates a feedback signal by superposing the control information onto the winding voltage information. The controller carries out the ON/OFF control of the switching element according to the feedback signal. | 10-04-2012 |
20120286679 | LIGHT EMITTING DEVICE CURRENT REGULATOR CIRCUIT AND CONTROL METHOD THEREOF - A light emitting device current regulator circuit is disclosed. A light emitting device circuit has a first end for receiving light emitting device operation power, and a second end. The light emitting device current regulator circuit includes: an internal voltage generation circuit coupled to the second end, for generating an internal voltage according to a second end voltage to supply electrical power to the light emitting device current regulator circuit, wherein the supply voltage generation circuit includes a charge storage device for storing charges from the second end voltage to generate the supply voltage; and a current control circuit coupled to the second end, the current control circuit regulating the light emitting device current according to a control signal, wherein the control signal at least intermittently reduces the light emitting device current to zero or low current in order to raise the second end voltage. | 11-15-2012 |
20120293084 | OPERATING CIRCUIT APPLIED TO BACKLIGHT AND ASSOCIATED METHOD - An operating circuit applied to a backlight is provided, where the backlight includes a plurality of lighting elements, and the operating circuit includes a plurality of current control circuits, a plurality of switches, a minimum voltage selector, a supply voltage generating circuit and a control unit. The current control circuits are coupled to the lighting elements via a plurality of nodes, respectively. The switches are coupled to the nodes, respectively. The minimum voltage selector is utilized for receiving at least a portion of voltages of the plurality of nodes, and selecting a minimum voltage among the received voltages. The supply voltage generating circuit is utilized for generating a supply voltage of the lighting elements according to the minimum voltage. For each of the switches, the control unit determines an on/off state of the switch by determining whether the corresponding lighting element is an open circuit or not. | 11-22-2012 |
20120306393 | TWO-TERMINAL CURRENT CONTROLLER AND RELATED LED LIGHTING DEVICE - An LED lighting device includes a first luminescent device for providing light according to a first current, a second luminescent device coupled in series to the first luminescent device for providing light according to a second current, an impedance device for limiting the second current within a predetermined range when a voltage established across the first luminescent device and the second luminescent device exceeds a first predetermined value, and a two-terminal current controller coupled in parallel with the first luminescent device and in series to the second luminescent device and configured to regulate the second current according to a voltage established across the two-terminal current controller. | 12-06-2012 |
20130002158 | TWO-TERMINAL CURRENT CONTROLLER AND RELATED LED LIGHTING DEVICE - An LED lighting device includes a first luminescent device for providing light according to a first current, a second luminescent device coupled in series to the first luminescent device for providing light according to a second current, a silicon-controlled rectifier coupled in parallel to the first luminescent device and configured to conduct a third current when a voltage established across the first luminescent device exceeds a break-over voltage, and a two-terminal current controller coupled in parallel with the first luminescent device and in series to the second luminescent device and configured to regulate the second current according to a voltage established across the two-terminal current controller. | 01-03-2013 |
20130026934 | LED CONTROL MODULE - A lighting system including a lighting module that receives a digital instruction stream containing lighting instructions, extracts a portion of the stream, provides a remainder of the stream to a connected adjacent lighting module, and executes the extracted portion. | 01-31-2013 |
20130038228 | DRIVER CICRUIT APPARATUS FOR AN LED STRING, LIGHT SOURCE APPARATUS AND INTEGRATED CIRCUIT - A driver circuit apparatus for light emitting diodes comprises a current mirror ( | 02-14-2013 |
20130043799 | LIGHT ENGINE WITH LED SWITCHING ARRAY - An LED array switching apparatus comprises, on a single PCB substrate: a plurality of LED arrays D | 02-21-2013 |
20130082616 | OVER-TEMPERATURE HANDLING FOR LIGHTING DEVICE - A lighting device employs at least one string of LEDs as a lighting source. The string of LEDs is coupled in series with a first switch, wherein the string of LEDs and the first switch are coupled between a power supply node and ground. During a normal operation mode, a system controller is configured to close the first switch to deliver a drive current to the string of LEDs from the power supply node. The system controller is further associated with a temperature sensor and is configured to detect an over-temperature condition based on information provided by the temperature sensor. Upon detecting the over-temperature condition, the system controller will open the first switch to stop the drive current from flowing through the string of LEDs. | 04-04-2013 |
20130088160 | Reconfigurable Multi-LED Light Source - A light having a plurality of LEDs and a switching substrate is disclosed. The switching substrate is coupled to LEDs and includes a plurality of switches that provide a plurality of configurations for the LEDs. Each configuration is characterized by a two-dimensional array of LEDs having a minimum bias potential and a maximum bias potential, the LED array generating light when a bias potential is provided between the power terminals that is greater than the minimum bias potential, at least two configurations being operable to provide light at bias potential within this range. The switching substrate is sub-dividable into a plurality of identical multi-LED light sources by dividing the switching substrate along predetermined lines. The array of LEDs can be organized as a nested array of LEDs. The switches can be implemented as passive switches that are set by removing portions of conductors or bridging gaps in conductors. | 04-11-2013 |
20130093340 | LIGHT EMITTING APPARATUS AND LED DRIVING METHOD USING THE SAME - Provided are a light emitting apparatus and a LED driving method using the same. The light emitting apparatus may include: a light source including first to nth LED groups driven by direct current (DC) power and sequentially connected in series; and a driving controller detecting a current flowing in an output terminal of the light source and changing the number of LED groups driven in the light source when the detected current is outside of a predetermined current range. | 04-18-2013 |
20130119877 | LIGHT SOURCE APPARATUS AND DRIVING APPARATUS THEREOF - A light source driving apparatus including a voltage converting unit, a switching unit, a feedback unit and a control unit is provided. The voltage converting unit provides a driving current to drive a light source module. The switching unit is controlled to be conducted or not by a switch signal. The feedback unit detects a load status of the light source module, and provides a feedback signal accordingly. The control unit modulates pulse widths of the switch signal according to the feedback signal, a signal upper limitation, and a signal lower limitation, so as to control the switching unit to be conducted. The voltage converting unit includes an energy storage element. When the switching unit is conducted, the energy storage element stores a part of energy provided by the input power source. When the switching unit is not conducted, the energy storage element provides the driving current. | 05-16-2013 |
20130127353 | Driving Circuits for Solid-State Lighting Apparatus With High Voltage LED Components and Related Methods - A driving circuit for a solid state lighting apparatus includes a full wave rectifier configured to rectify an alternating current (AC) input voltage signal to generate a rectified input signal, a boost conversion circuit configured to receive the rectified input signal and responsively generate a direct current (DC) output voltage signal and to supply the output voltage signal to a solid state light source, and a boost control circuit coupled to the boost conversion circuit and configured to cause the boost conversion circuit to operate in a constant power mode. | 05-23-2013 |
20130127354 | TWO-TERMINAL CURRENT CONTROLLER AND RELATED LED LIGHTING DEVICE - A two-terminal current controller having a current limiting unit and an adjusting unit regulates a first current flowing through a load according to a load voltage. When the load voltage does not exceed a first voltage, the two-terminal current controller operates in a first mode for conducting a second current associated a rectified AC voltage, thereby limiting the first current to zero and adjusting the second current accordingly. When the load voltage is between the first voltage and a second voltage, the two-terminal current controller operates in a second mode for conducting the second current, thereby limiting the first current to zero and limiting the second current to a constant value larger than zero. When the load voltage exceeds the second voltage, the two-terminal current controller operates in a third mode for turning off the current limiting unit. The adjusting unit can adjust the predetermined value and the second voltage. | 05-23-2013 |
20130134889 | Circuit for Driving Light Emitting Elements - In one novel aspect, driving a string of light emitting elements, such as LEDs, includes applying a drive signal to circuitry that regulates a voltage appearing at a source of a transistor whose drain is coupled to one end of the string of light emitting elements and whose source is coupled to ground through a resistive element. Sequencing of the drive signal and a voltage supply signal for the light emitting elements is controlled such that the voltage supply signal is not increased above a predetermined allowable voltage for the transistor until the transistor is turned on, and such that the supply voltage is not decreased below the allowable voltage for the transistor until the transistor is turned off. | 05-30-2013 |
20130154490 | CURRENT ROUTING TO MULTIPLE LED CIRCUITS - An illumination module includes a plurality of Light Emitting Diodes (LEDs) located in different zones to preferentially illuminate different color converting surfaces. The flux emitted from LEDs located in different zones may be independently controlled by selectively routing current from a single current source to different strings of LEDs in the different zones. In this manner, changes in the CCT of light emitted from LED based illumination module may be achieved. | 06-20-2013 |
20130162153 | Solid-State Lighting Apparatus Including Current Diversion Controlled by Lighting Device Bias States and Current Limiting Using a Passive Electrical Component - A lighting apparatus includes a string of light emitting diode (LED) sets coupled in series where each set includes at least one LED. A current diversion circuit is coupled to the string and is configured to operate responsive to a bias state transition of one of the LED sets to direct current away from another one of the LED sets. A current limiting circuit is coupled in series with the string and is configured to conduct current responsive to a forward biasing of all of the LED sets. The current limiting circuit includes only passive electrical component(s). | 06-27-2013 |
20130169175 | Continuous Step Driver - A light emitting diode (LED) lamp includes an LED cluster including LED groups arranged in series, a power source configured to provide an input power to the LED cluster, and a driving unit configured to adjust a number of the LED groups connected to a current path of the LED cluster in series based on the input power to the LED cluster. | 07-04-2013 |
20130181622 | UNIVERSAL TRY ME MODULE - A universal module capable of being removably coupled to each of a plurality of distinct products for demonstrating a functionality is described. In the universal module an activation switch is operatively coupled to a DC power source. An external electrical connector is operatively coupled to the DC power source and the activation switch. An external electrical connector is configured to removably couple the universal module to an external circuit of one of the plurality of distinct products. The circuit has an integrated circuit that is operatively coupled to the DC power source, the activation switch and the external electrical connector. When the external electrical connector is coupled to the external circuit and the activation switch is activated, the integrated circuit outputs a voltage from the DC power source through the external electrical connector to enable a functionality of a coupled product for a predetermined period of time. | 07-18-2013 |
20130181623 | POWER SOURCE APPARATUS AND LIGHTING APPARATUS - When a turn on signal or a turn off signal is input from a receiving unit to a controller, the controller outputs the turn on signal or the turn off signal to a voltage setting unit. When the turn on signal is input, the voltage setting unit sets an upper limit value of a voltage V | 07-18-2013 |
20130221861 | METHOD AND DEVICE FOR DRIVING AN LED STRING - The invention relates to a method and a device for driving an LED string of a first LED segment ( | 08-29-2013 |
20130249421 | Method for Optimizing Efficiency versus Load Current in an Inductive Boost Converter for White LED Driving - Circuits and methods to achieve a most efficient driver for white LEDs are disclosed. Switching Losses associated with the switching activity of a boost converter and mainly depending on clock frequency and total capacitance at the switching nodes and conduction losses associated with the current flowing in the boost converter and mainly depending on the series resistance of the elements in the regulation loop are minimized by using a size programmable NFET power switch with constant current limit, a very low voltage and accurate programmable current source, a programmable reference voltage for the error amplifier, and a PWM generator with programmable clock frequency. A limited number of configuration windows corresponding to a set of programmable values (OTP registers) for specific ranges of the current fed to the WLEDs. | 09-26-2013 |
20130249422 | VARIABLE MASTER CURRENT MIRROR - A variable master current minor circuit may be used to balance the currents through a parallel Light Emitting Diode (LED) strings in an illumination module when the LED string with the largest forward voltage changes due to events, such as a short failure of an LED. The variable master current mirror circuit includes a switching circuit that is coupled to the parallel LED strings and a current minor circuit that is coupled to the parallel LED strings and the switching circuit. The switching circuit switchably connects the LED string with the largest forward voltage to the current minor circuit as a master LED string. The current mirror circuit maintains equal currents through the LED strings with reference to the current through the master LED string. | 09-26-2013 |
20130257300 | LED lighting device with control means and method for operating the LED lighting device - It is the task of the present invention to provide an LED lighting device that is adapted for an AC voltage supply. | 10-03-2013 |
20130264958 | LIGHT-EMITTING DEVICE - A light-emitting device ( | 10-10-2013 |
20130285568 | LED LIGHT-EMITTING DEVICE, TERMINAL COUNT CONVERTER, AND ILLUMINATION APPARATUS - An LED light-emitting device includes: a three-terminal LED circuit which includes a first LED group constituted by a single light-emitting diode or a plurality of light-emitting diodes connected in series, a second LED group constituted by a single light-emitting diode or a plurality of light-emitting diodes connected in series, and an LED common terminal shared by anodes of the first LED group and the second LED group or cathodes thereof, and which has three terminals including both end terminals of the LED groups; and a three-terminal regulator circuit which includes a first regulating unit constituted by a unidirectional current regulator circuit, a second regulating unit constituted by a unidirectional current regulator circuit, and a regulator circuit common terminal connected with the first regulating unit and the second regulating unit and shared by anodes or cathodes thereof so as to exhibit a reverse polarity with respect to the three-terminal LED circuit. | 10-31-2013 |
20130293128 | LIGHT FIXTURE - A light fixture comprising a light emitting device, a first electrical path suitable for connecting the light emitting device to a first power circuit, a second electrical path suitable for connecting the light emitting device to a second power circuit and a connector element for acquiring a selected one of a first configuration and a second configuration. Wherein in the first configuration, the light emitting device is in electrical communication with the first electrical path for being powered by the first power circuit and in the second configuration, the light emitting device is in electrical communication with the second electrical path for being powered by the second power circuit. | 11-07-2013 |
20130293129 | Circuit arrangement for operating at least a first and a second cascade of LEDs - A circuit arrangement for operating at least a first and a second cascade of LEDs is provided. The LED cascades have a different number of LEDs, which are operated alternately in a manner adapted to the instantaneous value of the rectified AC supply voltage by a suitable drive logic. The cascades are assigned to LED units, wherein each unit includes a driving device for driving the respective cascade. The units are coupled in series between the two input terminals, wherein the input terminals are formed by the output of a rectifier. A linear regulator is provided in series with the cascades, said linear regulator being driven via a voltage divider coupled between the two input terminals. An auxiliary voltage supply is provided for operating the respective driving devices, wherein the auxiliary voltage is generated from the voltage dropped across the linear regulator during the operation of the circuit arrangement. | 11-07-2013 |
20130307424 | Device and Method for Driving an LED Light - An approach is provided for devices and methods for driving an LED light, which adjust the numbers of diodes of the LED string corresponding to the rectified AC voltage. The device comprises a power module, a LED string, a current source and a controller. The LED string has multiple LED diodes connected in series that forms a major segment and multiple minor segments. The controller is connected to the current source and the LED string, which selectively shorts the LED diodes of the minor segments. Since the number of LED diodes of the LED string is dynamically adjusted in response to the rectified voltage, the overall “on” voltage of the LED string is more closely matched to the rectified voltage, and thus the power efficiency is improved. | 11-21-2013 |
20130313987 | METHODS AND APPARATUS FOR SEGMENTING AND DRIVING LED-BASED LIGHTING UNITS - A plurality of LED-based lighting units is segmented into a plurality of LED-based lighting segments connected in series. Each lighting segment has a plurality of LED-based lighting units connected in series with at least a series-connection switch, and a bypass-connection switch is connected in parallel with the series of LED-based lighting units. The total number of LED-based lighting units can be determined by a maximum voltage level of an input voltage supply and the forward voltage of the LED-based lighting unit for achieving optimal efficiency. The number of lighting segments and the number of lighting units in each lighting segment are properly chosen based on the total number of the LED-based lighting units in such away that any number up to the total number of all the LED-based lighting units can be connected in series by respectively controlling the series-connection switch and the bypass-connection switch of each LED-based lighting segment. | 11-28-2013 |
20130313988 | Method and apparatus for controlling a multi-colored LED light string - A method and apparatus for controlling a light string is provided. A controller is coupled to the light string and is used to bias one or more of the multicolor LEDs within each bulb on the light string. Using a prearranged determination of 1) the multicolor LEDs within each bulb, 2) the placement of the bulbs within the light string, and 3) the proper biasing of the plurality of leads within the light string, the controller can be used to change the entire light string from one complex holiday color scheme to another using a simple switching mechanism to select from one a of a plurality of desired color schemes. | 11-28-2013 |
20130328492 | ELECTRONIC DEVICE AND CONTROL CIRCUIT APPLIED THERETO - A control circuit for an electrical load in an electronic device includes a voltage divider, a current measurement circuit, a variable-current-output switch and a comparison circuit, the voltage entering the load and the voltage (and thus current) exiting from the load being monitored and compared to a reference voltage, any difference causing the switch to dynamically adjust the level of current being supplied, to protect the load from sudden variations in power supply and ensure a stable and constant supply of power. | 12-12-2013 |
20130334975 | Controllers and Light Modules with Light Emitting Diodes - Disclosed are a controller and a relevant LED lighting module. A disclosed controller comprises a high-voltage power terminal and a low-voltage power terminal, a major switch circuit, an upward-connection terminal and a downward-connection terminal, and a management circuit. The major switch circuit is coupled between the high-voltage and low-voltage power terminals, and has a driving terminal for coupling to at least one LED. The management circuit is coupled to control the major switch circuit, and configured to communicate with an upstream controller via the upward-connection terminal and to communicate with a downstream controller via the downward-connection terminal. The upward-connection terminal is coupled to the downward-connection terminal of an upstream controller. The downward-connection terminal is coupled to the upward-connection terminal of a downstream controller. The management circuit is capable of operating in one of operation conditions. | 12-19-2013 |
20130334976 | LIGHT EMITTING DIODE DRIVING CIRCUIT AND DRIVING METHOD THEREOF - A LED string driving circuit includes a plurality of LED strings; a power supply unit configured to receive an input voltage and accordingly output a driving voltage to the LED strings; a comparison unit configured to receive the input voltage and output a first control signal according to a relationship between the input voltage and a predetermined voltage; a control unit configured to receive the first control signal and generate a second control signal according to a potential level of the first control signal; and a switch unit including a plurality of switch elements, and each are controlled by the second control signal and thereby forming various electrical loops and thereby configuring the LED strings corporately to form either a parallel loop or a series loop via the switch unit with respective electrical loops. A LED string driving method is also provided. | 12-19-2013 |
20130342119 | LED LAMP WITH VARIABLE INPUT POWER SUPPLY - There is provided a light emitting diode apparatus for operation with varying input electrical sources. The apparatus comprises an array of light emitting diodes to produce light, and a variable input power supply adapted to provide an electrical supply of predetermined value to the light emitting diodes from a varying electric signal provided by varying input electrical sources. In one embodiment, the light emitting diode apparatus is for use as a replacement of a fluorescent tube in an existing fluorescent fixture. In another embodiment, the light emitting diode apparatus is for use with connection to conventional AC voltage sources used throughout the world. | 12-26-2013 |
20130342120 | METHOD AND DEVICE FOR LIGHTING A SPACE USING AN LED STRING - In a method of lighting at least part of a space, a light emitting diode (LED) string is used. The LED string comprises a first LED segment and at least one further LED segment, which are connected in series, each LED segment comprising at least one LED. The LED string is powered by a rectified AC voltage. The first LED segment is powered when the rectified AC voltage is above a first voltage level, and the first LED segment and the further LED segment are powered when the rectified AC voltage is above a second voltage level higher than the first voltage level. The first LED segment is arranged to radiate light to a first volume of the space, and the further LED segment is arranged to radiate light to a second volume of the space, the first volume being at least partly different from the second volume. The first volume may at least partly overlap the second volume. | 12-26-2013 |
20140015429 | SYSTEMS AND METHODS FOR CURRENT MATCHING OF LED STRINGS - System and method are provided for regulating a string current flowing through a string of one or more light emitting diodes. A system controller includes a first controller terminal, a second controller terminal and a third controller terminal. The first controller terminal is coupled to a base terminal of a bipolar junction transistor, the bipolar junction transistor further including an emitter terminal and a collector terminal, the collector terminal being connected to the string of one or more light emitting diodes. The second controller terminal is coupled to the emitter terminal of the bipolar junction transistor and to a first resistor terminal of a resistor associated with a resistance. The third controller terminal is coupled to a second resistor terminal of the resistor. In addition, the system controller is configured to receive a reference voltage, receive an emitter voltage, and output a base current. | 01-16-2014 |
20140015430 | LED LIGHT SOURCE - A series arrangement of LED loads (LP | 01-16-2014 |
20140028205 | LED Controller with Current-Ripple Control - An LED controller and a method for controlling an LED device is disclosed. A current sense signal is representative of a load current flowing through the LED device. The current sense signal is compared with an upper threshold value and a lower threshold value. Current is provided to the LED device via an inductor coupled in series with the LED device when the current sense signal exceeds the upper threshold. A load current loop is closed over a free-wheeling diode when no current is provided to the LED device while the current sense signal is below the lower threshold. The upper threshold and the lower threshold are adjusted dependent on the current sense signal such that peak values of the current sense signal match corresponding desired peak values. | 01-30-2014 |
20140028206 | APPARATUS FOR CONTROLLING LED STRING - An apparatus for controlling an LED string is provided, in Which each high voltage (HV) N-type device has one end electrically connected or coupled with the corresponding LED unit and the other end coupled with a corresponding low voltage (LV) current limit switch via a corresponding path. The LV current limit switch is switched according to the voltage or current detected on the path. Since the current flowing through the HV N-type device increases or decreases with that flowing through the corresponding LV current limit switch, the HV N-type device will be indirectly controlled. | 01-30-2014 |
20140028207 | SINGLE INDUCTOR CONTROL OF MULTI-COLOR LED SYSTEMS - A circuit for driving multiple light emitting diodes (LEDs) includes at least two sets of LEDs, each set comprised of one or more LEDs in series. The circuit further includes a single inductor connected in series with the two sets of LEDs. At least one set of LEDs is connected to a shunting transistor connected in parallel with the set of LEDs. The duty cycle of the shunting transistor is controlled by a single controller connected to the shunting transistor and the inductor. | 01-30-2014 |
20140055050 | APPARATUS FOR DRIVING A PLURALITY OF SEGMENTS OF LED-BASED LIGHTING UNITS - An LED-based lighting apparatus includes a plurality of LED-based lighting segments connected in series with a current control device. Each lighting segment has at least one LED-based lighting unit connected in series. A plurality of switch controllers controlled by a switching voltage comparator unit is connected with the plurality of LED-based lighting segments to provide multiple operation modes for turning on different number of LED-based lighting segments. In one embodiment, each switch controller is connected in parallel with a corresponding segment. The switching voltage comparator unit generates a propagation signal that propagates through and controls the plurality of switch controllers. In the other embodiment, each switch controller is connected between a positive end of the corresponding segment and a current control device. The switching voltage comparator unit generates two propagation signals that propagate through and control the plurality of switch controllers. | 02-27-2014 |
20140055051 | LED Driver Having Priority Queue to Track Dominant LED Channel - An electronic circuit for driving a plurality of light emitting diode (LED) channels coupled to a common voltage node includes a priority queue for tracking a dominant LED channel. A queue manager may be provided to keep the priority queue updated during LED drive operations based on operating conditions associated with the LED channels. | 02-27-2014 |
20140077711 | Method and apparatus for controlling multi-colored light strings - A rotary switch is provided for controlling an attached light string containing a plurality of light colors. By manipulation of the control dial, a specially designed rotary board is rotated to provide electrical connection to the light string according to one of several present color patterns preprogrammed into the rotary board. The discrete rotary switch positions provided by the rotary switch allow for different color signaling patters to be provided at the output leads from the rotary switch so as to power a multicolored light staring with different patterns and create different multicolored effects. One of the discrete rotary switch positions permits the input color patter from an input light string to be passed through the rotary switch so as to provide the same color pattern at the output leads and power a multicolored light string with the same color pattern provided by the input light string. | 03-20-2014 |
20140077712 | LED DRIVING APPARATUS AND OPERATING METHOD THEREOF - A LED driving apparatus and an operating method thereof are disclosed. The LED driving apparatus includes a controller and an output stage. The output stage includes at least one LED, a switch, and a setup resistor. The at least one LED, the switch, and the setting resistor are coupled in series between an input voltage and ground. The controller is coupled to the input voltage and the switch respectively. The controller receives at least one voltage sensing signal and outputs a setup voltage signal to the output stage. The at least one voltage sensing signal is received from the node between the at least one LED and the switch, between two LEDs, or between two voltage dividing resistors coupled in series between the input voltage and ground. | 03-20-2014 |
20140097763 | APPARATUS FOR CONTROLLING THE OPERATION OF AN LED, AND METHOD FOR CONTROLLING DRIVE CURRENT THEREOF - The present invention relates to an apparatus for controlling the operation of an LED and to a method for controlling the drive current thereof. More particularly, the present invention relates to an apparatus for controlling the operation of an LED, which is capable of driving a direct current-operated LED module or an alternating current-operated LED module using alternating current power, and to a method for controlling the drive current of the apparatus. According to the present invention, the drive current of an LED array can be output in the form of a sine wave by a constant-current regulation or constant-power regulation even when input voltage varies, thus suppressing harmonics, improving the power factor, minimizing flicker, and preventing a temperature increase in the LED array and in an LED operation control circuit. | 04-10-2014 |
20140103825 | LED LIGHT SOURCE - A string of LED loads is supplied by means of a rectified mains voltage. A cathode of each LED load is coupled to ground by means of a string. The strings are made conductive and non-conductive one by one in dependency of the instantaneous value of the rectified mains using both voltage and current sensing. | 04-17-2014 |
20140125238 | APPARATUS FOR CONTROLLING LIGHT EMITIING DEVICES - A light emitting unit includes a plurality of light emitting devices. A control apparatus includes a rectifier for converting an alternating current (AC) signal into a ripple signal by rectifying the AC signal. A ripple signal adjuster reduces a level difference between maximum and minimum levels of the ripple signal, and outputs the resultant ripple signal as a drive signal. A turning-on controller controls turning-on of the light emitting devices in accordance with a level variation of the drive signal. | 05-08-2014 |
20140132166 | Circuit for Vehicle Lamps - The present invention provides a circuit for driving a vehicle lamp, comprising a dummy load. Multiple unidirectional conduction electronic components are coupled to the dummy, operable for conducting a current path to enable a current to flow through the dummy load. Each of multiple LED strings is coupled to each of the multiple unidirectional conduction electronic components, respectively. | 05-15-2014 |
20140145632 | LED DRIVE CIRCUIT - An LED drive circuit comprises a power supply unit, a first LED lamp string, a first voltage control unit, a second LED lamp string and a first power transfer unit. The power supply unit outputs a drive power to drive the first LED lamp string. The first voltage control unit gets the drive power and stabilizes and provides the voltage to the first LED lamp string. The first voltage control unit includes a power switch where the drive power generates a power loss. The second LED lamp string and first power transfer unit are coupled in series with the first voltage control unit so that the power loss is transferred and output to drive the second LED lamp string. Thus loss of the drive power is reduced and lighting efficiency of the LED improves. | 05-29-2014 |
20140152186 | LED BACKLIGHT DRIVING CIRCUIT, BACKLIGHT MODULE, AND LCD DEVICE - A light emitting diode (LED) backlight driving circuit includes a light bar and a power supply module that is coupled with the light bar. The light bar and the power supply module are connected by a flexible circuit board. The light bar is also connected with a measuring resistor in series. A test point is arranged at two ends of the measuring resistor. | 06-05-2014 |
20140159597 | LIGHTING SYSTEM AND CONTROL METHOD THEREOF - A lighting system includes: a rectifier full-wave rectified an AC voltage to generate an output voltage; first and second LED groups connected to each other in series, wherein an input terminal of the first LED group is coupled to the output voltage; first terminals of first and second switches respectively coupled to output terminals of the first and second LED groups; a first resistor having a first terminal connected to the second terminal of the first switch and the second switch and a second terminal connected to a ground voltage; and first and second operational amplifiers having output terminals respectively coupled to control terminals of the first and second switches, and inverting input terminals respectively coupled to the first terminal of the first resistor, and non-inverting input terminals respectively coupled to the first and second reference voltages. | 06-12-2014 |
20140159598 | LED CURRENT CONTROL - An LED control circuit for controlling a current supplied to an LED unit is disclosed. A sense resistor is included for sensing an output current provided from an output node. A comparator circuit is provided for detecting upper and lower thresholds in the output current based on the voltages at ends of the sense resistor, and for controlling a current supply to maintain the current between the thresholds. The comparator circuit comprises a reference current source and reference resistors, for generating upper and lower threshold references. The comparator circuit further comprises a comparator for detecting a mid-range voltage dependent on the output current and deriving a control signal which indicates if the detected voltage is above or below the mid-range voltage. The control signal is used to adjust the reference current source, thereby to vary the upper and lower threshold references to maintain a constant median or average output current. | 06-12-2014 |
20140159599 | FLICKER-FREE LAMP DIMMING-DRIVER CIRCUIT FOR SEQUENTIAL LED BANK CONTROL - An LED dimmer circuit to sequentially control multiple banks of LEDs connected in series. The invention is designed to respond to demands for more or less illumination by sequentially turning on or off one or more banks of LEDs. Each bank is turned off or on in response to the phase angle of an AC power source with each LED bank being controlled by a different phase angle. | 06-12-2014 |
20140159600 | LED-BASED LAMP WITH USER-SELECTABLE COLOR TEMPERATURE - A lamp including a first set of light emitting diodes configured to generate first light, a second set of light emitting diodes configured to generate second light, and a third set of light emitting diodes configured to generate third light. The first light, the second light, and the third light combine to produce white light. A first switch is located at a base portion of the lamp. The state of the first switch corresponds to a color temperature of the white light. A color temperature adjustment module is configured to vary outputs of the first, second, and third sets of light emitting diodes in accordance with the color temperature of the white light selected by a user using the first switch. | 06-12-2014 |
20140167633 | BACKLIGHT DRIVING CIRCUIT AND LIQUID CRYSTAL DISPLAY WITH THE SAME - A backlight driving circuit is disclosed. The backlight driving circuit includes a steady voltage circuit, a boost converter, a current setting circuit, and a control circuit. The steady voltage circuit receives an input voltage, filters the input voltage and outputs a steady DC voltage. The boost converter connects to the steady voltage circuit to receive the steady DC voltage. The control circuit provides a first PWM square wave such that the boost converter may supply power to the LED light bar. Wherein the boost converter includes a first MOSFET or a triode. At least three parallel connected resistors are arranged between a source of the first MOSFET or a collector of the triode and the ground, and the three resistors have the same or similar resistance. In addition, a liquid crystal display includes the backlight driving circuit is also disclosed. | 06-19-2014 |
20140191675 | SYSTEM AND METHOD FOR CONTROLLING A LIGHT EMITTING DIODE FIXTURE - One embodiment in accordance with the invention can include a circuit for controlling a light emitting diode (LED) lighting fixture via a power line. The circuit can include a power switch coupled to the power line and is for outputting a firing angle. Additionally, the circuit can include a control circuit coupled to the power switch and is for implementing firing angle control of the power switch. Furthermore, the circuit can include a translator coupled to receive the firing angle and for mapping the firing angle to a function of the LED lighting fixture. | 07-10-2014 |
20140191676 | LED ARRANGEMENT - An LED arrangement includes a first LED chain having first LEDs; a second LED chain having second LEDs; a circuit arrangement for coupling the first and second LED chains to a supply source; wherein the circuit arrangement is configured such that the first and second LED chains can be coupled to or decoupled from the supply source, wherein the first LED chain can be coupled to the supply source at first points in time and the second LED chain can be coupled to the supply source at second points in time; wherein the circuit arrangement is configured such that, in the case of a coupling of the LED arrangement to the supply source, a current having a first average current intensity through the first LED chain and a current having a second average current intensity through the second LED chain, wherein the LEDs are arranged depending on their current intensities. | 07-10-2014 |
20140191677 | LIGHT EMITTING MODULE AND LIGHTING UNIT INCLUDING THE SAME - A light emitting module includes a body, first to M | 07-10-2014 |
20140191678 | POWER CONVERTER FOR AN LED ASSEMBLY AND LIGHTING APPLICATION - A power converter for an LED assembly includes a switched mode power supply arranged to power the LED assembly, an AC/DC converter arranged to provide a DC supply voltage to the switched mode power supply, and a control unit arranged to receive an input signal representing a required load voltage for powering the LED assembly. The control unit is arranged to control the AC/DC converter based on the input signal. | 07-10-2014 |
20140197752 | CURRENT DRIVER FOR AN ARRAY OF LED DIODES - An array of LED diodes includes N channels each having LEDs coupled in series with a switch. A current driver for the array includes a processing circuit configured to detect N currents flowing respectively through the N channels of the array. The detected currents are converted by a single analog to digital converter, one at a time, into a digital word. The circuit further includes N comparator devices configured to control the N switches as result of a comparison between the digital words and respective target digital words. A memory is provided for storing the digital words received from the analog to digital converter. | 07-17-2014 |
20140203720 | METHOD OF FORMING A CURRENT CONTROLLER FOR AN LED AND STRUCTURE THEREFOR - In one embodiment, an LED current controller is formed to determine which of a plurality of LED branches has the largest voltage drop and to select the current through that branch to use in controlling the value of current that flows through other LED branches. | 07-24-2014 |
20140210369 | SOLID STATE LIGHT AC LINE VOLTAGE INTERFACE WITH CURRENT AND VOLTAGE LIMITING - An analog electronic circuit for driving a string of LEDs including input terminals for accepting connection to AC voltage, a current regulation circuit operatively coupled to receive an AC voltage from the input terminals and to provide an output for connection to drive the string of LEDs. Included is a current regulation circuit configured to limit the current flow through the string of LEDs on a half-cycle basis to a predetermined value. Also disclosed is an over voltage circuit configured to switch off electrical connection between the AC voltage and the string of LEDs upon the AC reaching a predetermined high voltage value on a half-cycle basis. | 07-31-2014 |
20140232278 | LIGHT EMITTING DIODE DRIVER - A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes: a string of LEDs divided into n groups, the n groups of LEDs being electrically connected to each other in series, a downstream end of group m−1 being electrically connected to the upstream end of group m, where m is a positive number equal to or less than n. The driver circuit also includes a plurality of current regulating circuits, each of the current regulating circuits being coupled to the downstream end of a corresponding group at one end and coupled to the ground at the other end and including a sensor amplifier and a cascode having first and second transistors, each sensor amplifier being coupled to a different voltage source for providing a different reference voltage thereto. | 08-21-2014 |
20140246984 | BALLAST WITH CURRENT CONTROL CIRCUIT - A ballast configured to connect to a set of lamps to energize the set of lamps is provided. The ballast comprises an inverter circuit for generating an oscillating power signal, wherein the oscillating power signal has a frequency, and a resonant tank circuit electrically connected to the inverter circuit for receiving the oscillating power signal and therefrom providing a lamp current to the set of lamps. A resistance circuit is connected to the inverter circuit. The resistance circuit has a resistance that defines the frequency of the oscillating power signal generated by the inverter circuit. A current control circuit is connected to the resistance circuit for adjusting the resistance of the resistance circuit as a function of a number of lamps that are connected to the ballast. | 09-04-2014 |
20140252968 | LIGHT EMITTING DIODE DRIVER - A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes: a string of LEDs divided into n groups, the n groups of LEDs being electrically connected to each other in series, a downstream end of group m-1 being electrically connected to the upstream end of group m, where m is a positive number equal to or less than n. The driver circuit also includes a plurality of current regulating circuits, each of the current regulating circuits being coupled to the downstream end of a corresponding group at one end and coupled to the ground at the other end and including a sensor amplifier and a cascode having first and second transistors, each sensor amplifier being coupled to a different voltage source for providing a different reference voltage thereto. | 09-11-2014 |
20140265894 | Cascade led driver and control methods - An electrical circuit is disclosed and methods for controlling the same. The electrical circuit may comprises a plurality of color strings coupled in series, where each color string has at least one lamp, preferably a light emitting diode. Improved efficiency may be accomplished in some embodiments using certain of the disclosed systems and methods. | 09-18-2014 |
20140285098 | MULTI-CHANNEL LED DRIVER ARRANGEMENTS - LED driver arrangements are disclosed comprising: an input; a plurality of switched mode boost converters, each connected to the input; and a plurality of outputs, each output having a different voltage and being for driving at least one LED string; wherein each of the plurality of switched mode boost converters is configurable to output of any one of the plurality of outputs. Controllers for such arrangements are also disclosed. | 09-25-2014 |
20140292216 | CIRCUIT AND METHOD FOR INDEPENDENT CONTROL OF SERIES CONNECTED LIGHT EMITTING DIODES - Described herein is a circuit and method for independent control of series connected light emitting diodes (LEDs). The circuit includes a first light emitting diode (LED) connected in series with a second LED. A current source is connected in series with the first LED and the second LED and a shunt circuit is connected in parallel with the first LED and the second LED. The shunt circuit includes a pair of serially connected resistors. The shunt circuit prevents inadvertent excitement of the LEDs due to leakage currents but minimally affect illumination characteristics of the LEDs. A pair of transistors is connected to the first LED and the second LED, respectively, and is biased using a set of bias resistors. A tri-state control signal switches on and off the pair of transistors and enables excitation of the first LED, the second LED or both via the current source. | 10-02-2014 |
20140292217 | DIMMING SYSTEM OF LAMP USING LIGHT-EMITTING DEVICE - A dimming system of a lamp using a light-emitting device includes: a power source including a power input terminal, a dimmer connected to the power input terminal, and a rectifier circuit; a lighting unit including light-emitting devices from a first light-emitting device to an n | 10-02-2014 |
20140292218 | TRANSISTOR LED LADDER DRIVER WITH CURRENT REGULATION AND OPTICAL FEEDBACK FOR LIGHT EMITTING DIODES - Ladder network circuits ( | 10-02-2014 |
20140306614 | SELF-ADAPTIVE DRIVE CIRCUIT AND LED LAMP WITH THE SAME - The invention relates to a technical field of light emitting diodes (LEDs), in particular to a self-adaptive drive circuit and an LED lamp with the same. The LED lamp comprises a plurality of series LED lamp strings, and each LED lamp string comprises at least one series LED lamp bead; and the self-adaptive drive circuit comprises a rectifying unit, a current limiting unit, a voltage detection and connectivity control unit and at least one controllable switch unit. According to the self-adaptive drive circuit and the LED lamp with the same, the LEDs can be driven normally in an extremely simple drive mode, which can work without using complex constant current drive circuit and electrolytic capacitor that is life limiting. At the same time, the stroboflash phenomenon is eliminated, the power factor is improved, harmonic distortion is reduced, electromagnetic interference is eliminated, and the cost is reduced. | 10-16-2014 |
20140312793 | APPARATUS FOR DRIVING LEDS USING HIGH VOLTAGE - An apparatus for driving LEDs using high voltage includes a plurality of LEDs divided into a plurality of LED segments connected in series and a plurality of three-terminal voltage controlled current limiting devices. Each of the current limiting devices is associated with one of the LED segments and has a first terminal connected to a negative end of the associated LED segment, a second terminal applied with a bias voltage and a third terminal connected to a common node. A current source is connected between the common node and ground. A power-loss reduction circuit having a plurality of LEDs controlled by an LED controlling circuit may further be inserted between the common node and the current source to reduce the power loss in the current source because of the high voltage at the common node. | 10-23-2014 |
20140320031 | VARIABLE POWER DIMMING CONTROL CIRCUIT - Disclosed is a variable power dimming control circuit for driving and linearly adjusting the illumination brightness of a plurality of light emitting diodes (LEDs), and the circuit includes a dimming stabilization unit and a control unit. The control unit is provided for detecting an input current of a circuit, and the dimming stabilization unit is driven for outputting a holding current when the input power is smaller than a standard, and stopping the output the holding current when the input power is greater than the standard. When the LEDs are dimmed to low luminance, a chip controls the operation of the dimming stabilization unit to assure the stability of the dimming operation of a TRIAC. When the LEDs are adjusted to high or full brightness, the chip stops the output of the holding current to reduce unnecessary power consumption and enhance the overall circuit performance effectively. | 10-30-2014 |
20140320032 | CONTROLLING AN LED STRING USING A CURRENT SINK WITH LOW SIDE VOLTAGE REGULATION - A method of controlling an LED string having a first end coupled to a power source and a second end coupled to a first end of a current sink is provided. The method include generating a target voltage at a first end of an external inductor coupled to the second end of the current sink, comparing the target voltage to a measured voltage at the first end of the external inductor, charging the external inductor responsive to the measured voltage being greater than the target voltage, and discharging the external inductor responsive to the measured voltage being less than the target voltage. | 10-30-2014 |
20140327365 | A CONSTANT CURRENT SOURCE CIRCUIT AND A SAMPLING CIRCUIT - A constant current source circuit includes a main circuit, wherein the main circuit includes a first three-terminal regulator, a transistor, a sample resistor and a load, an output terminal of the first three-terminal regulator is connected with a control Electrode of the transistor, a reference Electrode of the transistor is connected with a voltage input terminal, a working Electrode is connected with one end of the load, and the other end of the load is connected with one end of the sample resistor, and the other end of the sample resistor and an input terminal of the first three-terminal regulator are connected to a reference potential, respectively, wherein the constant current source circuit further includes an adjusting unit that includes a voltage stabilizing unit, a fourth resistor and a fifth resistor. | 11-06-2014 |
20140333220 | LIGHT EMITTING DIODE DRIVER - A driver circuit for driving light emitting diodes (LEDs). The driver circuit includes a string of LEDs divided into n groups and the n groups of LEDs is electrically connected to each other in series, where a downstream end of group m−1 is electrically connected to the upstream end of group m. The driver circuit also includes a power source coupled to an upstream end of group 1 and provides an input voltage. The driver circuit further includes current regulating circuits, where each of the current regulating circuits is coupled to the downstream end of the corresponding group at one end and coupled to a ground at the other end. Each of the current regulating circuits includes a sensor amplifier and a cascode having first and second transistors. The driver circuit also includes detectors, where each of the detectors detects a source voltage of the first transistor. | 11-13-2014 |
20140339993 | LIGHT EMITTING DIODE DRIVING APPARATUS AND LIGHT EMITTING DIODE BACKLIGHT SYSTEM USING THE SAME - A light emitting diode (LED) driving apparatus and an LED backlight system using the same are provided. The backlight control circuit suitable for driving an LED string includes a complex function pin, a driving circuit and a backlight control circuit. The backlight control circuit includes a control current generating unit, a first current comparing unit and a second current comparing unit. The control current generating unit receives a dimming control signal and an enable control signal from the complex function pin to generate a control current accordingly. The first and the second current comparing units are respectively configured to compare the control current with first and second predetermined currents to respectively generate a first and a second control signals. The driving circuit determines to be turned on or off according to the second control signal, and further adjusts a luminance of the LED string according to the first control signal. | 11-20-2014 |
20140339994 | LIGHTING MODULE - A lighting module includes a power line for receiving a power supply current and a ground line, a segmentation point for cutting the lighting module into two parts, a first set of light sources upstream of the segmentation point, a second set of light sources downstream of the segmentation point, wherein the first and second sets of light sources are connected in series, and a resistive element connected to the intermediate point between the first and the second set of light sources, and the ground line, which is configured in such a way that: when the lighting module has not been cut, the resistive element has a resistance which is greater than the resistance of the portion of the lighting module downstream of the segmentation point, and when the lighting module has been cut, the resistive element has a resistance which is less than the resistance thereof. | 11-20-2014 |
20140346962 | SWITCHED-CAPACITOR ISOLATED LED DRIVER - A switched-capacitor voltage converter which is particularly well-suited for receiving a line voltage from which to drive current through a series of light emitting diodes (LEDs). Input voltage is rectified in a multi-level rectifier network having switched capacitors in an ascending-bank configuration for passing voltages in uniform steps between zero volts up to full received voltage V | 11-27-2014 |
20140354163 | LED DRIVING DEVICE - An LED driving device includes: a rectifying circuit for outputting a DC voltage to a string of M LED units; (M−1) first switching circuits each coupled between a corresponding one of first to (M−1) | 12-04-2014 |
20140354164 | LIGHT-EMITTING DIODE LIGHTING DEVICE HAVING MULTIPLE DRIVING STAGES - An LED lighting device includes a slave driving stage and a master driving stage. The slave driving stage includes a first luminescent device and a first current controller for providing a constant current setting in an ON phase. The master driving stage includes a second luminescent device and a current control unit having a second current controller and a current envelope controller. The second current controller provides a current envelope in the ON phase. The current envelope controller sets a level of the current envelope according to a rectified AC voltage. The driving current is regulated by the first current controller according to the constant current setting when the constant current setting is smaller than the level of the current envelope, or by the second current controller according to the current envelope when the level of the current envelope is smaller than the constant current setting. | 12-04-2014 |
20140361698 | LED CONVERTER INCLUDING A RESONANT CONVERTOR - The invention relates to an LED converter for operating a load comprising at least one LED series that includes at least one LED, preferably multiple LEDs. On the primary side, the LED converter comprises a resonant converter supplied with a direct current voltage. The resonant converter has a half-bridge that is constructed of two reciprocally clocked switches and that provides a supply voltage for the LED series through a serial/parallel resonance circuit connected to the midpoint of said half-bridge. To regulate the power transferred by the LED converter to the LED series as a feedback factor in each switch-on cycle, a control unit is designed to directly or indirectly determine a peak value of the feedback factor through the lower-potential switch of the half-bridge and to adjust the clocking of the half-bridge, i.e. the frequency and/or the duty factor, as a control factor. | 12-11-2014 |
20140375224 | ILLUMINATION APPARATUS INCLUDING SEMICONDUCTOR LIGHT EMITTING DIODES - An illumination apparatus capable of controlling current amounts of LEDs and enabling various electrical connections is provided. An applied driving voltage is divided, and a divided voltage is compared with a reference voltage to generate sampling signals. A logic operation is performed on the sampling signals to generate a switch control signal and a current control signal. The switch control signal controls electrical connection of LEDs to which the driving voltage is applied. Also, the current control signal may select LEDs that are to perform light emitting operations. A target voltage is set by processing the sampling signals and used to determine driving currents of the LEDs that are to perform the light emitting operations. | 12-25-2014 |
20150008837 | DRIVER CIRCUIT FOR LIGHT-EMITTING DIODES - In one embodiment, a driver circuit for light-emitting diodes has a first DC/DC converter (DCDC | 01-08-2015 |
20150022104 | LED LIGHTING APPARATUS HAVING IMPROVED FLICKER PERFORMANCE - Provided is a lighting apparatus using LEDs (light-emitting diodes having improved flicker performance. In general, in a direct-drive LED lighting apparatuses of the related art which use no switching-mode power supply (SMPS), percent flicker (hereinafter referred to as “% F”) is 100%. In contrast, the % F of the LED lighting apparatus having improved flicker performance according to the present invention is 40% or less that is equivalent to the % F of fluorescent lamps using a magnetic ballast. | 01-22-2015 |
20150028756 | LED BACKLIGHT DRIVING CIRCUIT AND LIQUID CRYSTAL DEVICE - A LED backlight driving circuit is disclosed. The driving circuit includes a boost circuit for converting an input voltage to a needed output voltage and for providing the output voltage to at least one LED strings, a follower circuit connecting to a negative end of the LED string, and a reference voltage module connecting to a reference voltage and the follower circuit. The follower circuit is for detecting a negative end voltage of the LED string and for generating a follower voltage according to the negative end voltage. The follower voltage couples with a reference voltage module. The reference voltage module adjusts the output voltage according to the follower voltage generated by the follower circuit. The output voltage is adjusted in accordance with the voltage drop of the LED string. In addition, a liquid crystal device including the LED backlight driving circuit is also disclosed. | 01-29-2015 |
20150042234 | DYNAMICALLY RECONFIGURABLE LED DRIVERS AND LIGHTING SYSTEMS - LED drivers and lighting systems having a dynamically reconfigurable switching network is disclosed. The lighting system comprises a switching network which provides interconnections between LEDs or LED lamps that can dynamically reconfigure between largely parallel circuits and largely serial circuits as the instantaneous voltage of a power supply varies. When the instantaneous voltage of the power source is low, the switching network interconnects the LED lamps in a largely parallel configuration. As the instantaneous voltage increases, the switching network reconfigures and interconnects the LED lamps with increasing serial configurations. As the instantaneous voltage begins to decrease, the switching network reconfigures and interconnects the LED lamps back to a largely parallel configuration. | 02-12-2015 |
20150048749 | ORNAMENTAL LIGHTING SYSTEM - A lighting system includes a first light string configured to receive a first voltage and output continuous illumination, a second light string, a module electrically connected to the second light string, and a controller electrically connected to the module. The controller receives a user input and outputs a control signal based on the user input. The module receives the control signal and selectively controls a second voltage to the second light string according to the control signal. | 02-19-2015 |
20150077000 | LIGHTING SOURCE AND LIGHTING APPARATUS - An LED lamp according to one aspect of the present invention including: a first LED array including first LED elements connected in series; a second LED array that includes second LED elements connected in series and emits light having an emission color different from an emission color of the first LED array; a FET switch that is provided between the two LED arrays and switches between a first current path to the first LED array and a second current path to the second LED array; a constant power output circuit that outputs the same power value to a current path through which current flows before the switching and a current path through which current flows after the switching, wherein a total forward voltage of the first LED array is different from a total forward voltage of the second LED array. | 03-19-2015 |
20150077001 | LIGHTING SOURCE AND LIGHTING APPARATUS - A straight tube LED lamp according to one aspect of the present invention includes: a first LED array including first LED elements connected in series; a second LED array that includes second LED elements connected in series, and emits light having a different emission color from an emission color of the first LED array; a FET switch provided in a path through which current flows to the second LED array; and a constant power output circuit that outputs power without changing a total value of the power, wherein the number of the first LED elements connected in series is greater than the number of the second LED elements connected in series, a total forward voltage of the first LED array is greater than a total forward voltage of the second LED array, and the first LED elements are in alignment with the second LED elements. | 03-19-2015 |
20150077002 | LIGHTING SOURCE AND LIGHTING APPARATUS - An LED lamp according to one aspect of the present invention includes: a first LED array that is annularly arranged on a mounting board and includes first LED elements connected in series; a second LED array that is arranged within an inner circumference of the first LED array on the mounting board, includes second LED elements connected in series, and emits light having an emission color different from an emission color of the first LED array; a FET switch arranged in series on a path through which current flows to the second LED array; and a constant power output circuit, wherein the number of the first LED elements is greater than the number of the second LED elements, and a total forward voltage of the first LED array is greater than a total forward voltage of the second LED array. | 03-19-2015 |
20150091455 | LED DRIVER - A LED driver is disclosed herein. In one embodiment, the LED driver comprises a rectifier circuit, a driving current generating circuit, a bus voltage detection circuit, a LED configuration control circuit, and a LED array. The LED driver according to the present disclosure reconfigures the prior LED array, balances usage of each LED by switching operation of each LED, which results in long lifetime of the LED driver while reducing power dissipation or increasing a PF value. | 04-02-2015 |
20150115818 | LED DRIVING CIRCUIT - A LED (Light-Emitting Diode) driving circuit including at least one light-emitting unit and a protection detecting circuit, is provided. Each light-emitting unit includes an LED string coupled to a driving voltage, a current regulator and a transistor. The current regulator is coupled to a corresponding LED string and controls a current flowing therethrough. The transistor is coupled between the LED string and the current regulator. The protection detecting circuit generates a clamping reference level signal to a control terminal of the at least one transistor and is coupled to a connection node of the at least one transistor and the at least one LED string. When a voltage of any connection node is higher than a preset protection value, the protection detecting circuit decreases the clamping reference value to reduce or cut off the current of the at least one LED string. | 04-30-2015 |
20150115819 | LIGHT EMITTING DIODE DRIVING APPARATUS - A light emitting diode driving apparatus may include: a light emitting diode emitting light by receiving rectified power; a driver driving the light emitting diode based on a voltage level of the rectified power; and a controller limiting an operation of the driver based on a voltage applied to the driver and a hysteresis reference value. | 04-30-2015 |
20150115820 | APPARATUS AND METHOD FOR DRIVING LED - A light emitting diode (LED) driving apparatus may include: a rectifying unit providing a rectified voltage; an LED array including at least one LED string including first to nth LEDs connected in series; a sink path controller providing first to (n−1)th sink path control signals according to a level of the rectified voltage; a sink path switching circuit unit including first to (n−1)th sink path switches performing a switching operation according to each of the first to (n−1)th sink path control signals; a voltage phase controller generating a phase-adjusted voltage; a source path controller providing first to (n−1)th source path control signals; and a source path switching circuit unit including first to (n−1)th source path switches performing a switching operation according to each of the first to (n−1)th source path control signals. | 04-30-2015 |
20150123552 | Overvoltage Protection Circuit, LED Backlight Driving Circuit and LCD - An OVP circuit includes a voltage boost circuit, for boosting an input voltage into an output voltage in need and providing the output voltage to a load, a voltage control module for controlling the voltage boost circuit to boost an input voltage into an output voltage in need and for providing the output voltage to the load, an overvoltage protection module for monitoring a voltage of a positive terminal of the load to enable or disable the voltage control module, and an overvoltage adjusting module for monitoring an operation voltage of the load to adjust the overvoltage. It effectively prevents from the abnormal operation attributed by over practical operation voltage or prevents components from damage attributed by tardy protection. The present invention also proposes an LED backlight driving circuit using the OVP circuit and an LCD having the LED backlight driving circuit. | 05-07-2015 |
20150305101 | DEVICE FOR CONTROLLING A STORAGE DEVICE - A device for controlling the amount of energy stored in a storage device comprises a control unit that is adapted to adjust the power received via an input of the device, based on the amount of energy currently stored in the storage device, and that is further adapted to output the adjusted power via an output of the device to the storage device. | 10-22-2015 |
20150312986 | LIGHTING MEANS INSERTION DETECTION - In a first aspect, the invention provides an LED converter, comprising: a resonant converter with a switching regulator, preferably a clocked half-bridge converter, a galvanic barrier, the primary side of which being supplied by the switching regulator and the secondary side of which being arranged for providing directly or indirectly power to terminals for connecting one or more LEDs, a control circuit on the primary side of the galvanic barrier of the resonant converter, a sensing means on the secondary side of the galvanic barrier sensing a secondary side electric parameter indicative of an LED load, when connected to said terminals, a feedback path from the sensing means to the control circuit adapted to feedback the secondary side electric parameter from the secondary side of the galvanic barrier to the primary side of the galvanic barrier, wherein in case no LED string is connected to the LED converter, the control unit is adapted to cyclically control a switching frequency of switching regulator switches, in particular switches of the clocked half-bridge, from a high frequency to a lower frequency, and to monitor whether the secondary side electric parameter reaches a predetermined threshold value, and to, in case the predetermined threshold value is reached, deactivate the switching regulator switches and to activate a voltage protection switch to pull the secondary side electric parameter to ground. | 10-29-2015 |
20150334802 | DEVICE FOR DRIVING LIGHT EMITTING DIODE MODULE AND METHOD FOR DRIVING LIGHT EMITTING DIODE MODULE - A device for driving a light emitting diode (LED) module is disclosed, wherein alternating current (AC) power is rectified and applied to an LED module and brightness of the LED module is adjusted by adjusting the maximum value of an LED current passing through the LED module, thereby achieving natural brightness adjustment. The device for driving an LED module may include a driver, a control signal receiver, a control signal converter, and a linear circuit. | 11-19-2015 |
20150351169 | DIGITALLY CONTROLLED DRIVER FOR LIGHTING FIXTURE - The present disclosure relates to a lighting fixture that is capable of providing white light over an extended range of correlated color temperatures. | 12-03-2015 |
20150359049 | DRIVING CIRCUITRY FOR LED LIGHTING WITH REDUCED TOTAL HARMONIC DISTORTION - Conditioning circuits are provided for driving two or more LED groups using a rectified AC input voltage. The conditioning circuits uses analog circuitry to gradually and selectively activate the LED groups based on an instantaneous value of the rectified input voltage. The circuit includes a first series interconnection of a first LED group, a first transistor, and a first resistor, and a second series interconnection of a second LED group, a second transistor, and a second resistor. In one example, the second series interconnection is connected between a drain terminal and a source terminal of the first transistor, while in another example, the second series interconnection is connected between an anode of the first LED group and a source terminal of the first transistor. The first and second LED groups are selectively activated by the rectified voltage applied across the first series interconnection. | 12-10-2015 |
20150366032 | RETAINING CIRCUIT AND LIGHT EMITTING DEVICE DRIVER CIRCUIT WITH RETAINING CIRCUIT - A retaining circuit includes: a low dropout regulator (LDO) circuit for generating a primary operation voltage, a secondary operation voltage generation (SOVG) circuit, and a memory circuit. The SOVG circuit generates a secondary operation voltage, and the memory circuit is powered by the secondary operation voltage to store at least one operation parameter, such that when the primary operation voltage is lower than a non-controlled level, the memory circuit holds the operation parameter to sustain operation. | 12-17-2015 |
20150382409 | SEQUENTIAL LINEAR LED DRIVER UTILIZING HEADROOM CONTROL - A sequential linear light emitting diode (LED) driver utilizing a headroom control technique is disclosed. | 12-31-2015 |
20150382420 | LED DRIVE CIRCUIT - The purpose of the present invention is to provide an LED drive circuit that is capable of ameliorating insufficient lighting and improving power utilization efficiency. This LED drive circuit is an LED drive circuit wherein the number of LEDs that are turned on varies in accordance with the voltage of a commercial alternating-current power supply, the LED drive circuit being characterized by having an LED row in which multiple LEDs are connected in series, a current detection resistor for detecting a current that flows in the LED row, a bypass circuit that is connected to an intermediate connection part of the LED row, and a current-limiting circuit that is connected to an end of the LED row, wherein the bypass circuit includes a first current-limiting component, the current-limiting circuit includes a second current-limiting component, the first current-limiting component is controlled on the basis of a voltage across the ends of the current detection resistor or a voltage that is obtained by dividing the voltage across the ends of the current detection resistor, and the second current-limiting component is controlled by the divided voltage that is obtained by dividing the current detection resistor. | 12-31-2015 |
20160007428 | INTEGRATED LIGHT-EMITTING DIODE DRIVER CIRCUIT AND METHOD OF OPERATING THE SAME - An integrated light-emitting diode (LED) driver circuit includes a bi-directional power line communication (PLC) unit, a power conversion module, and a constant current (CC)/constant voltage (CV) control unit. The bi-directional PLC unit receives an AC voltage, and converts a modulation signal on the AC voltage to generate a light-dimming control signal. The power conversion module receives the AC voltage and converts the AC voltage to generate an output voltage. The CC/CV control unit receives the light-dimming control signal to generate a dimming constant current or a dimming constant voltage. The integrated LED driver circuit outputs the dimming constant current or the dimming constant voltage and the output voltage to drive a LED string. | 01-07-2016 |
20160029444 | LIGHTING DEVICE AND LIGHT FIXTURE - A controller circuit is configured to adjust the number of light-emitting diodes that a current flows from a rectifier circuit through so that: the number of light-emitting diodes, which are lit, of the plurality of light-emitting diodes increases according to a value of a pulsating voltage during a time period that the value of the pulsating voltage increases; and the number of light-emitting diodes, which are lit, of the plurality of light-emitting diodes decreases according to the value of the pulsating voltage during a time period that the value of the pulsating voltage decreases. Light-emitting diodes, which start to emit light by a higher voltage value, of the plurality of light-emitting diodes are disposed at a position nearer to an outside of a mounting region of a substrate than light-emitting diodes, which start to emit light by a lower voltage value, of the plurality of light-emitting diodes. | 01-28-2016 |
20160029445 | UNIVERSAL INPUT LED DRIVER - A universal AC-line input light emitting diode (LED) drive includes a rectifier, at least one LED connected to one output of the rectifier, a controllable element in series with the at least one LED, and a circuit for turning off the controllable element when the line voltage exceeds a reference voltage. The reference voltage is selected to produce the average current through the LEDs when the line voltage is nominally 120VAC, 240VAC, or 277VAC. Another circuit may also be provided for switching the reference voltage between at least two levels (e.g., two of 120VAC, 240VAC, or 277VAC) when an average line voltage exceeds a certain level. | 01-28-2016 |
20160029451 | LED Driver Circuit - An LED driver circuit includes at least one string ( | 01-28-2016 |
20160029455 | CURRENT FEEDBACK FOR IMPROVING PERFORMANCE AND CONSISTENCY OF LED FIXTURES - A lighting system includes a power converter connected to mains voltage and configured to provide a driving current responsive to a control signal. A voltage measurement circuit is configured to provide a voltage sense signal indicative of an amplitude of the mains voltage. A light-emitting diode (LED) module includes at least one string of LEDs that emit light responsive to the driving current, and is configured to detect an LED current through the at least one string and output a current feedback signal indicative of the detected LED current. A driver controller is configured to output the control signal responsive to the voltage sense signal and the current feedback signal. | 01-28-2016 |
20160037592 | DRIVING DEVICE FOR LED AND THE DRIVING METHOD THEREOF - The present invention discloses a driving device for LED and the driving method thereof, includes: a bridge rectifier, at least one LED-lamp bunch and LED-lamp group and P-type switching module and N-type driving module, and a logic controller; the LED-lamp bunch and group are connected orderly in series; the bridge rectifier's positive end connects to the LED-lamp bunch's anode, while a negative end gets grounded; the logic controller connects to the anode and cathode of LED-lamp bunch through the P-type switching module respectively, the cathode of LED-lamp group through N-type driving module, and the negative input end of the bridge rectifier; by controlling the N-type driving module and P-type switching module makes the number of lit-on LED-lamps change following the rectified input signal voltage changes; thus its efficiency is improved and easy to be integrated into chips. | 02-04-2016 |
20160100463 | LIGHT EMITTING DEVICE DRIVER CHIP - The present invention discloses a light emitting device driver chip for driving light emitting devices in series. The chip includes: plural pins electrically connected to corresponding light emitting devices, respectively, wherein an internal voltage is provided through a predetermined one of the pins; a voltage regulation circuit for providing an operation voltage according to the internal voltage; a switch circuit including plural switch groups electrically connected to corresponding pins, respectively; a current source circuit for providing a current to the light emitting devices; and a switch control circuit for controlling the switch groups to determine which light emitting device is turned ON. The light emitting device driver chip does not directly receive the rectified input voltage. | 04-07-2016 |
20160100469 | LIGHTING DEVICE HAVING DIFFERENT OLEDS IN SERIES AND SHUNTING SWITCH FOR SUBSET OF OLEDS - A lighting device is described. The lighting device | 04-07-2016 |
20160119995 | SIGNAL SMOOTHING DEVICE AND BACKLIGHT DEVICE INCLUDING THE SAME - A signal smoothing device includes: a plurality of capacitors connected in parallel between a conductive line and ground; a plurality of switches connected in series between the conductive line and each capacitor; and a switch selector configured to select one of the switches and to turn on the selected switch, based on a signal applied to the conductive line. | 04-28-2016 |
20160128145 | SECOND STAGE CALIBRATION IN DC/DC LED CURRENT REGULATION - A current regulator controller includes a differential amplifier that is arranged to output a current sense signal based on a differential input signal and a first stage trim signal. The current regulator controller also includes a first stage trim circuit that is arranged to provide the first stage trim signal. The current regulator controller also includes a digital-to-analog converter that is arranged to provide a set signal based on a digital input signal and a second stage trim signal. The current regulator controller also includes a second stage trim circuit that is arranged to provide the second stage trim signal. The current regulator controller also includes an error amplifier that is arranged to output an error signal based on the set signal and the current sense signal. The regulation of the current is based on the error signal. | 05-05-2016 |
20160143102 | VOLTAGE/CURRENT REGULATOR SUPPLYING CONTROLLED CURRENT WITH PVT ADJUSTED HEADROOM - A voltage/current regulator supplying controlled current with PVT headroom adjustment. In an example application, an LED backlight driver controls ILED string current, and controls a voltage regulator supplying VOUT string voltage with sufficient headroom voltage VHDRM to supply the ILED string current. The LED driver controls ILED string current with an MLED current control transistor, including gate drive referenced to a reference voltage VREF. VOUT/VHDRM are adjusted for PVT operating conditions by generating a replica/reference current ILED/RATIO (proportional to ILED string current) with a replica current control transistor MLED/RATIO based on VREF. ILED/RATIO is mirrored to a second replica MLED/RATIO transistor that saturates at a PVT_REF reference voltage corresponding to a minimum voltage that can supply the required ILED current (as represented by the ILED/RATIO replica/reference current), accounting for PVT operating conditions. | 05-19-2016 |
20160150605 | LIGHTING APPARATUS - Disclosed is a lighting apparatus for reducing total harmonic distortion (THD). The lighting apparatus may include a lighting unit having a plurality of LED groups divided into first and second lighting groups, and the lighting unit may provide a current path for light emission corresponding to a change of a rectified voltage, using two or more drives having the same structure. | 05-26-2016 |
20160157312 | Drivers and Driving Methods for a LED String, Capable of Providing LED Short Protection or Avoiding LED Flickering | 06-02-2016 |
20160192447 | DEVICE FOR CONTROLLING A FIELD EFFECT TRANSISTOR - A device for actuating at least one field effect transistor corresponding to a control signal present at a control line, includes at least one driver circuit having a current mirror with an input side and an output side. Both the input side and the output side are connected to a supply voltage, the input side is connected to the control line via a level converter and the output side is connected to the at least one FET. | 06-30-2016 |
20160255691 | LED DRIVER | 09-01-2016 |
20160381751 | LIGHT EMITTING DEVICE (LED) DRIVING APPARATUS AND LIGHTING DEVICE INCLUDING THE SAME - A light emitting diode (LED) driving apparatus includes a power supply circuit configured to supply driving power to a plurality of LED arrays, a controller integrated circuit (IC) including a plurality of internal switches respectively connected to the plurality of LED arrays and configured to control a path of current flowing in the plurality of LED arrays by adjusting operations of the plurality of internal switches based on a magnitude of the driving power, and a current control circuit connected to an output terminal of a first LED array among the plurality of LED arrays and configured to adjust current flowing in the first LED array. The first LED array is constantly operated while the driving power is being supplied. | 12-29-2016 |