Patent application number | Description | Published |
20080238397 | Circuit and method for soft start of a switching regulator from a residual voltage - For soft start of a switching regulator, the output voltage of the switching regulator is fed back to be compared with a ramp signal, in order to trigger a comparison signal when the ramp signal rises up to reach the feedback signal, to enable the switching regulator such that the output voltage changes from a residual voltage toward a target value. The low side switch of the switching regulator is kept off for a period of time after the switching regulator is enabled, so as to prevent a reverse current during the soft start period. | 10-02-2008 |
20090039704 | Simple circuit and method for improving current balance accuracy of a power converter system - A power converter system includes multiple converter modules connected to a share bus. Each of the converter modules mirrors the phase current of itself to provide a mirror current to the share bus, extracts an average current from the share bus, and compares the phase current of itself with the average current it extracts from the share bus to produce an output signal for modulation of the phase current of itself. Specifically, each of the converter modules is provided with a resistor connected to the share bus such that all the resistors are connected in parallel, and thus each of the resistors automatically receives an average current from the share bus. | 02-12-2009 |
20100320844 | POWER OFF DELAY CIRCUIT AND METHOD, AND AUDIO SYSTEM WITH POWER OFF DELAY - A power off delay circuit includes a switch connected between an external power input terminal and an internal power supply terminal, a capacitor connected to the internal power supply terminal, and a hysteresis comparator to switch the switch according to the voltages of the external power input terminal and the internal power supply terminal. During on-time of the switch, the external power input terminal is connected to the internal power supply terminal and the capacitor can be charged by the external power source. When the switch is off, the capacitor provides electric power for an internal circuit. Application of the power off delay circuit to an audio system may eliminate the turn-off pops of the audio system. | 12-23-2010 |
20100321849 | OVERSTRESS PROTECTION APPARATUS AND METHOD - An overstress protection apparatus includes a switch detector. The switch is arranged in a grounding path of a load system. The detector detects the current, voltage or temperature of the load system to determine a signal for controlling the switch, to thereby protect the load system working in normal conditions. | 12-23-2010 |
20110068761 | AVERAGE CURRENT REGULATOR AND DRIVER CIRCUIT THEREOF AND METHOD FOR REGULATING AVERAGE CURRENT - The present invention discloses an average current regulator, a driver circuit of an average current regulator, and a method for regulating an average current. The average current regulator includes: a power stage including at least one power transistor which switches according to a pulse width modulation (PWM) signal to convert an input voltage to an output current; a feedback circuit coupled to the power stage, for generating a feedback signal; an ON-time controller coupled to the feedback circuit, for receiving the feedback signal and generating an ON-time signal according to the feedback signal and an average reference signal relating to a target average current; and a PWM controller, for generating the PWM signal according to the ON-time signal to regulate the average of the output current to the target average current. | 03-24-2011 |
20110109238 | Digital dimming device and digital dimming method - The present invention discloses a digital dimming device and a digital dimming method, for controlling a plurality of light emitting device channels. The method comprises: generating a corresponding plurality of driving signals to control the plurality of light emitting device channels; receiving a PWM input signal having a duty ratio, and phase shifting the PWM input signal to generate multiple PWM output signals with about the same duty ratio as the PWM input signal, but with respectively shifted phases; and enabling or disabling corresponding driving signals by the multiple PWM output signals, respectively. | 05-12-2011 |
20110109290 | FREQUENCY CONTROL CIRCUIT AND METHOD FOR A NON-CONSTANT FREQUENCY VOLTAGE REGULATOR - A non-constant frequency voltage regulator includes a constant-time trigger to generate a pulse width modulation signal, a current generator to provide a first current to set a constant on-time or a constant off-time for the pulse width modulation signal, and a frequency control circuit to detect the pulse width of a phase node voltage, compare the pulse width with the constant on-time or the constant off-time set by the first current to generate a second current, and add the second current to the first current to supply to the constant-time trigger to control the frequency of the pulse width modulation signal. | 05-12-2011 |
20110109291 | FREQUENCY CONTROL CIRCUIT AND METHOD FOR A NON-CONSTANT FREQUENCY VOLTAGE REGULATOR - A non-constant frequency voltage regulator includes a constant-time trigger to trigger a constant on-time or a constant off-time for a pulse width modulation signal, a current generator to provide a first current to determine the constant on-time or the constant off-time, a power output stage operated by the pulse width modulation signal to produce a load current, and a frequency control circuit for loading feed forward by a second current added to the first current to adjust the constant on-time or the constant off-time for frequency compensation to the pulse width modulation signal. | 05-12-2011 |
20110109398 | FIXED-FREQUENCY CONTROL CIRCUIT AND METHOD FOR PULSE WIDTH MODULATION - A fixed-frequency control circuit and method detect the difference between the frequency of a pulse width modulation signal and a target frequency to adjust a current used to determine the on-time or off-time of the pulse width modulation signal, such that the frequency of the pulse width modulation signal is stable at the target frequency. | 05-12-2011 |
20110187430 | Multi-Chip Module with Master-Slave Analog Signal Transmission Function - The present invention discloses a multi-chip module with master-slave analog signal transmission function. The multi-chip module comprises: a master chip having a first setting input pin for receiving an analog setting signal to generate an analog setting in the master chip, and the master chip duplicating the analog setting to output a first analog output; and a first slave chip for receiving the first analog output from the master chip to generate an internal setting of the first slave chip. | 08-04-2011 |
20110233716 | CIRCUIT STRUCTURE OF AN ULTRA HIGH VOLTAGE LEVEL SHIFTER - A circuit structure of an ultra high voltage level shifter includes a low voltage substrate having the electronic elements of the ultra high voltage level shifter thereon, an ultra high voltage redistribution layer, and a passivation layer between the substrate and the redistribution layer to prevent dielectric breakdown between the redistribution layer and the substrate. | 09-29-2011 |
20120008345 | APPARATUS AND METHOD FOR OUTPUT VOLTAGE CALIBRATION OF A PRIMARY FEEDBACK FLYBACK POWER MODULE - An apparatus and method for output voltage calibration of a primary feedback flyback power module extract the difference between the output voltage of the power module and a target value, and according thereto, calibrate a reference voltage which is used in regulation of the output voltage, to thereby calibrate the output voltage to be the target value. | 01-12-2012 |
20120056683 | FREQUENCY JITTER CIRCUIT AND METHOD - An oscillator generates a clock signal according to a voltage, a current and a capacitance, and a frequency jitter circuit and method use a random number to modulate the voltage, the current or the capacitance, or a count value to modulate the capacitance, to jitter the frequency of the clock signal. | 03-08-2012 |
20120155122 | CONTROLLER AND CONTROLLING METHOD FOR POWER CONVERTER - A controller for a power converter is provided. The controller includes a sense current integrating circuit, a reference current integrating circuit and a drive signal generation circuit. The sense current integrating circuit performs an integrating operation to a sense current representative of a conduction current flowing through a power switch of the power converter and thereby outputs a first integrating result. The reference current integrating circuit performs another integrating operation to a reference current and thereby outputs a second integrating result. The drive signal generation circuit determines a switching period of the power switch according to a status of an output voltage of the power converter cooperative with a relative magnitude relationship between the first integrating result and the second integrating circuit. Furthermore, a controlling method for such power converter also is provided. | 06-21-2012 |
20120155123 | REVERSE SHUNT REGULATOR - A reverse shunt regulator includes a MOSFET connected between a cathode and an anode, a switch and a current source serially connected between the cathode and the anode, and an error amplifier having a positive input node to receive an internal reference voltage, a negative input node connected to the reference electrode, and an output node connected to a control electrode of the MOSFET. When the voltage of the reference electrode is within a range, the larger the voltage of the reference electrode is, the less the current of the MOSFET is. Application of this reverse shunt regulator to a flyback converter for output feedback will reduce the power loss in a green mode of the flyback converter. | 06-21-2012 |
20120229165 | CONFIGURATION AND METHOD FOR IMPROVING NOISE IMMUNITY OF A FLOATING GATE DRIVER CIRCUIT - A floating gate driver circuit includes a level shifter, a pass element, a bistable circuit and a control logic circuit, to shift the voltage level of a control signal from a lower one to a higher one. The level shifter or the pass element has loads dynamically controlled by the control logic circuit to filter malfunction caused by dv/dt noise induced by a floating node. | 09-13-2012 |
20120306459 | Power Factor Correction Circuit, Control circuit Therefor and Method for Driving Load Circuit through Power Factor Correction - The present invention discloses a power factor correction circuit, a control circuit therefor and a method for driving a power factor correction circuit. The power factor correction circuit receives rectified power obtained by rectifying AC power, and corrects the power factor thereof. The power factor correction circuit includes an inductor, and it generates a reference signal as a limit for the inductor current. The reference signal is proportional to Comp/Vin, wherein Comp is a signal relating to a feedback signal, and Vin is a voltage signal relating to the AC power or the rectified power. | 12-06-2012 |
20130063216 | POWER OFF DELAY CIRCUIT AND METHOD, AND AUDIO SYSTEM WITH POWER OFF DELAY - A power off delay circuit includes a switch connected between an external power input terminal and an internal power supply terminal, a capacitor connected to the internal power supply terminal, and a hysteresis comparator to switch the switch according to the voltages of the external power input terminal and the internal power supply terminal. During on-time of the switch, the external power input terminal is connected to the internal power supply terminal and the capacitor can be charged by the external power source. When the switch is off, the capacitor provides electric power for an internal circuit. Application of the power off delay circuit to an audio system may eliminate the turn-off pops of the audio system. | 03-14-2013 |
20130070379 | POWER REGULATOR WITH OVER CURRENT PROTECTION AND CONTROL CIRCUIT THEREOF AND METHOD OF OVER CURRENT PROTECTION - The present invention discloses a power regulator with over current protection (OCP), a control circuit thereof, and a method of over current protection. The power regulator with OCP includes: a primary circuit, a transformer, and a secondary circuit. The power regulator receives AC power, and generates secondary current which is supplied to a load circuit. The primary circuit includes a control circuit which includes: a switch control circuit, a first comparator circuit, a sample and hold circuit, and a compensation circuit which is coupled to the sample and hold circuit. The compensation circuit adaptively adjusts a threshold level of the OCP according to a current sense signal, or controls a delay time of an over current detection signal to compensate an error of the OCP threshold level, which is caused by the AC power, such that the primary current may have a peak corresponding to a predetermined setting. | 03-21-2013 |
20130106466 | HIGH VOLTAGE OFFSET DETECTION CIRCUIT | 05-02-2013 |
20130113450 | MIXED MODE COMPENSATION CIRCUIT AND METHOD FOR A POWER CONVERTER - A mixed mode compensation circuit and method for a power converter generate a digital signal according to a reference value and a feedback signal which is related to the output voltage of the power converter, convert the digital signal into a first analog signal, offset the first analog signal with a variable offset value to generate a second analog signal, and filter out high-frequency components of the second analog signal to generate a third analog signal for stable output voltage of the power converter. The mixed mode compensation does not require large capacitors, and thus the circuit can be integrated into an integrated circuit. | 05-09-2013 |
20130162359 | FREQUENCY JITTER CIRCUIT AND METHOD - An oscillator generates a clock signal according to a voltage, a current and a capacitance, and a frequency jitter circuit and method use a random number to modulate the voltage, the current or the capacitance, or a count value to modulate the capacitance, to jitter the frequency of the clock signal. | 06-27-2013 |
20130169370 | FREQUENCY JITTER CIRCUIT AND METHOD - An oscillator generates a clock signal according to a voltage, a current and a capacitance, and a frequency jitter circuit and method use a random number to modulate the voltage, the current or the capacitance, or a count value to modulate the capacitance, to jitter the frequency of the clock signal. | 07-04-2013 |
20130176758 | MOSFET BRIDGE RECTIFIER - A bridge rectifier is established by MOSFETs instead of diodes. The MOSFET bridge rectifier includes a voltage detector to detect the voltages of two AC input terminals of the MOSFET bridge rectifier, for identifying the positive and negative half cycles of an AC voltage input to the MOSFET bridge rectifier, thereby accurately controlling the MOSFETs. | 07-11-2013 |
20130207704 | CIRCUIT AND METHOD FOR IMPROVING NOISE IMMUNITY OF A SINGLE-END LEVEL SHIFTER IN A FLOATING GATE DRIVER - A floating gate driver uses a single-end level shifter to translate a set signal and a reset signal induced by a rising edge and a falling edge of a switch signal to a common output terminal to generate an output voltage for a bistable circuit to generate a level shifted switch signal. Under control of a well transient detect signal asserted by detecting noise in the output voltage, a masking circuit between the single-end level shifter and the bistable circuit masks noise in the output voltage. This configuration has lower area penalty and better noise immunity. | 08-15-2013 |
20130229207 | FLOATING GATE DRIVER WITH BETTER SAFE OPERATION AREA AND NOISE IMMUNITY, AND METHOD FOR LEVEL SHIFTING A SWITCH SIGNAL - A floating gate driver includes a level shifter to transmit a set signal and a reset signal to a first output terminal and a second output terminal, respectively. The level shifter includes a first high-voltage transistor, a first current limiter and a first input transistor connected in series between the first output terminal and a ground terminal, and a second high-voltage transistor, a second current limiter and a second input transistor connected in series between the second output terminal and the ground terminal, and the first and second high-voltage transistors are remained on. With this arrangement, the level shifter can transmit signals from low side to high side under better safe operating area and has better noise immunity. | 09-05-2013 |
20130234790 | CONTROL CIRCUIT FOR POWER CONVERTER AND METHOD THEREOF - A control circuit for a power converter is disclosed, having a shared pin, a driving circuit, a current source, a sampling circuit, and a signal processing circuit. The shared pin is used for coupling with an output end of the power converter through a resistor. The driving circuit is used for conducting a switch of the power converter. The current source provides a current to the resistor through the shared pin. The sampling circuit samples the signal on the shared pin for generating a first sampling value and a second sampling value. When the difference between the first sampling value and the second sampling value is less than a predetermined value, the signal processing circuit configures the driving circuit to adjust at least one of the conduction time and the conduction frequency of the switch according to an output signal of the power converter received from the shared pin. | 09-12-2013 |
20130235633 | CONTROL CIRCUIT FOR POWER CONVERTER AND METHOD THEREOF - A control circuit for a power converter has a current source, a sampling circuit, a signal processing circuit, a driving circuit, and a shared pin. The shared pin is used for coupling with a resistor and a switch. The current source, coupled with the shared pin, provides a current through the shared pin to the resistor in a first period. The sampling circuit, coupled with the shared pin, samples signals on the shared pin for generating a first sampling value and a second sampling value. The signal processing circuit, coupled with the sampling circuit, compares the first sampling value and the second sampling value. The driving circuit generates driving signals for conducting the switch. When the difference of the first sampling value and the second sampling value is less than a predetermined value, the signal processing circuit configures the driving circuit to intermittently conduct the switch in a second period. | 09-12-2013 |
20130342127 | LED CONTROL DEVICE FOR PHASE-CUT DIMMING SYSTEM AND CONTROL METHOD THEREOF - An LED control device for configuring a phase-cut dimming system includes an LED and a switch. The LED control device configures the conduction status of the switch so as to supply power to the LED according to an input signal. The LED control device further detects whether the input signal is phase-cut. When the input signal is phase-cut, the LED control device stores the signal values of the internal circuits. Afterward, when the input signal is not phase-cut, the LED control device restores the stored signal values so that the internal circuits may resume to the previous operation status rapidly. | 12-26-2013 |
20140022010 | CONTROL CIRCUIT FOR POWER CONVERTER AND METHOD THEREOF - A control circuit for a power converter includes a shared pin, a driving circuit, a current source, a sampling circuit, and a signal processing circuit. The shared pin is coupled with an output end of the power converter through a resistor. The driving circuit conducts a switch of the power converter. The current source provides a current to the resistor through the shared pin. The sampling circuit samples the signal on the shared pin for generating a first sampling value and a second sampling value. The signal processing circuit calculates a first difference between the first sampling value and a first reference value, and a second difference between the second sampling value and a second reference value. When the difference between the first difference and the second difference is less than a predetermined value, the signal processing circuit may therefore configure the conduction time or frequency of the switch. | 01-23-2014 |
20140042515 | HIGH VOLTAGE DEVICE - The present invention provides a high voltage device including a shielding metal layer to reduce the noise interference from a high voltage source. The high voltage device includes a substrate, a field oxide layer, a gate layer, a shielding metal layer, and a high voltage interconnection line. The substrate includes a first doped region and a second doped region separated from each other. The field oxide layer is disposed on the substrate. The gate layer is disposed above the field oxide layer. The high voltage interconnection line is coupled to the first doped region and passes above but not below the first shielding metal layer. | 02-13-2014 |
20140056036 | AC-TO-DC POWER CONVERTER AND CONTROL METHOD AND CONTROL INTEGRATED CIRCUIT THEREOF - An AC-to-DC power converter with a BJT as a power switch can set a base current of the BJT by a current setting resistor which is in the outside of a control integrated circuit. Since an output current and a recovery current of the BJT are injected into a sensing resistor, the AC-to-DC power converter can correctly detect an inductor current thereof from the sensing resistor. | 02-27-2014 |
20140118029 | HIGH VOLTAGE OFFSET DETECTION CIRCUIT - A high voltage half-bridge driver circuit has a high voltage terminal and a floating node to be connected with a high side switch therebetween. When turning on the high side switch, a high voltage offset detection circuit detects a voltage related to the voltage at the floating node for triggering a zero voltage switching signal. | 05-01-2014 |
20140139043 | Power Off Delay Circuit and Method, and Audio System with Power Off Delay - A power off delay circuit includes a switch connected between an external power input terminal and an internal power supply terminal, a capacitor connected to the internal power supply terminal, and a hysteresis comparator to switch the switch according to the voltages of the external power input terminal and the internal power supply terminal. During on-time of the switch, the external power input terminal is connected to the internal power supply terminal and the capacitor can be charged by the external power source. When the switch is off, the capacitor provides electric power for an internal circuit. Application of the power off delay circuit to an audio system may eliminate the turn-off pops of the audio system. | 05-22-2014 |
20140192564 | SWITCHING POWER CONVERTING APPARATUS - A switching power converting apparatus is capable of converting an input voltage to an output voltage, and includes a transformer, a primary side control module, and a secondary side control module. The secondary side control module utilizes voltage clamping techniques or current-drawing techniques to stop self-excited conversion from the input voltage to the output voltage when the output voltage is greater than a predetermined target voltage, or utilizes a non-self-excited conversion architecture. | 07-10-2014 |
20140253185 | CIRCUIT AND METHOD FOR IMPROVING NOISE IMMUNITY OF A SINGLE-END LEVEL SHIFTER IN A FLOATING GATE DRIVER - A floating gate driver uses a single-end level shifter to translate a set signal and a reset signal induced by a rising edge and a falling edge of a switch signal to a common output terminal to generate an output voltage for a bistable circuit to generate a level shifted switch signal. Under control of a well transient detect signal asserted by detecting noise in the output voltage, a masking circuit between the single-end level shifter and the bistable circuit masks noise in the output voltage. This configuration has lower area penalty and better noise immunity. | 09-11-2014 |
20140268924 | CONTROL CIRCUIT FOR FLYBACK POWER CONVERTER AND CALIBRATION METHOD THEREOF - A control circuit of a flyback power converter includes a first reference signal generating circuit for generating a first reference signal; a reference signal adjusting circuit for generating an adjustment signal according to the first reference signal and a test signal corresponding to an output voltage signal of the flyback power converter, and to generate a second reference signal according to the adjustment signal and the first reference signal; an error detection circuit for generating an error signal according to the second reference signal and a feedback signal; and a control signal generating circuit for generating a control signal according to the error signal to control operations of a power switch to thereby adjust the test signal. The feedback signal corresponds to a current flowing through a primary side coil of the power converter or a sensing voltage of an inductive coil of the power converter. | 09-18-2014 |
20140286057 | SWITCHING POWER CONVERTING APPARATUS, SWITCHING CONTROLLER FOR THE SAME, AND METHOD OF CONTROLLING A BIPOLAR JUNCTION TRANSISTOR OF THE SAME - A switching power converting apparatus includes a coil unit, a bipolar junction transistor (BJT) controlling power transfer through the coil unit, and a current sensing resistor sensing a current flowing through the BJT so as to produce a sensed voltage thereacross. A switching controller includes a current source supplying a first current, a current generating module generating, based on an input voltage associated with the sensed voltage, a second current, which is proportional to the current flowing through the BJT, a multiplexing module selecting one of the first and second currents as an output current, and a driving module outputting, based on the output current, a driving current, which is proportional to the output current, to the BJT to thereby conduct the BJT. | 09-25-2014 |
20140328087 | Apparatus and Method for Implementing a Multiple Function Pin in a BCM Power Supply - An apparatus and a method for implementing a multiple function pin in a boundary conduction mode power supply, uses a same pin to switch a power switch and to achieve zero current detection to reduce pin count and save cost of a control integrated circuit. A first voltage is applied to the multiple function pin to turn on the power switch, and then a second voltage is applied to the multiple function pin after the power switch has been turned on for a first time, to thereby turn off the power switch. After the power switch has been turned off for a second time, a third voltage is applied to the multiple function pin keep the power switch off. Preferably, a tristate output driver is used to provide the first and second voltages, and a clamping circuit is used to provide the third voltage. | 11-06-2014 |