STMicroelectronics (Shenzhen) R&D Co. Ltd Patent applications |
Patent application number | Title | Published |
20160142024 | ADVANCED CURRENT LIMIT FUNCTION FOR AUDIO AMPLIFIER - A class-D audio amplifier incorporates an overcurrent protection scheme implementing two overcurrent thresholds to avoid a dynamic impedance drop. When output current reaches the first threshold as a result of an impedance drop across the speaker, the overcurrent protection circuitry limits the output current to the value of the first threshold, but does not shut down the circuit. The second threshold is used to detect an overcurrent condition to shut down the circuit. Current limiting logic of a first channel monitors the overcurrent condition of a second channel and controls the first channel output in response thereto. This permits the second channel output current to reach the second threshold if the circuit is experiencing a short-circuit condition. This scheme also allows the output current to drop below the first threshold if the overcurrent condition of the second channel is caused by an impedance drop across the output speaker. | 05-19-2016 |
20160119999 | DRIVING APPARATUS FOR A LIGHT EMITTING DEVICE AND METHOD FOR THE SAME - A driving apparatus configured to drive a light emitting device includes a driving current source module operable to supply current to the light emitting device via a node during operation. A protection module coupled to the node and the driving current source module selectively injects current to the node during operation. The driving current source module is controlled based on a detection result of a voltage on the node. | 04-28-2016 |
20160118894 | INVERTING BUCK-BOOST CONVERTER DRIVE CIRCUIT AND METHOD - A driver circuit includes a high-side power transistor having a source-drain path coupled between a first node and a second node and a low-side power transistor having a source-drain path coupled between the second node and a third node. A high-side drive circuit, having an input configured to receive a drive signal, includes an output configured to drive a control terminal of said high-side power transistor. The high-side drive circuit is configured to operate as a capacitive driver. A low-side drive circuit, having an input configured to receive a complement drive signal, includes an output configured to drive a control terminal of said low-side power transistor. The low-side drive circuit is configured to operate as a level-shifting driver. | 04-28-2016 |
20160103463 | SWITCHING CONVERTER TO OPERATE IN PULSE WIDTH MODULATION MODE OR PULSE SKIPPING MODE - An electronic device may include a switching converter configured to convert an input voltage to an output voltage, and being selectively operable in a pulse skipping mode based upon a control signal. The switching converter may include a comparator having a first input configured to receive an error signal, a second input configured to receive a skipping mode reference signal, and an output configured to generate the control signal. A reference generator may be configured to generate the skipping mode reference signal as a function of a difference between the output voltage and the input voltage. | 04-14-2016 |
20160100468 | BIDIRECTIONAL VOLTAGE DIFFERENTIATOR CIRCUIT - A bidirectional voltage differentiator circuit comprises start-up circuitry, sensing circuitry, and output circuitry coupled to logic circuitry. The start-up circuitry acts to start-up the sensing circuitry when the circuit is powered on, and accelerates the response of the sensing circuitry thereafter. The sensing circuitry senses variation in an input voltage applied to an input node. Responsive to the voltage variation sensed by the sensing circuitry, the output circuitry produces a state change at a first or second output node. The logic circuitry receives the states of the output nodes and produces a logic output signal to indicate the occurrence of the variation sensed in the input voltage. The voltage sensing circuit is operable to sense variation of the input voltage regardless of whether the voltage is rising or falling and without regard to the DC value of the input voltage. | 04-07-2016 |
20160065148 | ADVANCED CURRENT LIMIT FUNCTION FOR AUDIO AMPLIFIER - A class-D audio amplifier incorporates an overcurrent protection scheme implementing two overcurrent thresholds to avoid a dynamic impedance drop. When output current reaches the first threshold as a result of an impedance drop across the speaker, the overcurrent protection circuitry limits the output current to the value of the first threshold, but does not shut down the circuit. The second threshold is used to detect an overcurrent condition to shut down the circuit. Current limiting logic of a first channel monitors the overcurrent condition of a second channel and controls the first channel output in response thereto. This permits the second channel output current to reach the second threshold if the circuit is experiencing a short-circuit condition. This scheme also allows the output current to drop below the first threshold if the overcurrent condition of the second channel is caused by an impedance drop across the output speaker. | 03-03-2016 |
20160065066 | BOOST CONVERTER WITH CIRCUIT TO CONTROL THE BODY OF THE BOOST OUTPUT RECTIFICATION TRANSISTOR AND METHOD - A first softstart signal indicates operation in a load phase for a boost rectifier and a second softstart signal indicates operation in a pulse drive phase which follows the load phase. A rectification transistor is actuated for the duration of the load phase in response to the first softstart circuit to generate a rising output voltage. The rectification transistor is further repeatedly actuated during the pulse drive phase in response to the second softstart circuit to generate a boosted output voltage. A first transistor coupled between a first conduction terminal and a body terminal of the rectification transistor is actuated, and a second transistor coupled between the body terminal and a second conduction terminal of the rectification transistor is deactuated, during the load phase. The first transistor is deactuated, and the second transistor is actuated, during the pulse drive phase. | 03-03-2016 |
20160062384 | CURRENT STEERING MODE DIGITAL-TO-ANALOG CONVERTER CIRCUIT CONFIGURED TO GENERATE VARIABLE OUTPUT CURRENT - A current source circuit is configured to receive a reference current at the input circuit path of a current mirror circuit. The current mirror circuit mirrors the reference current and generates mirror currents at a number of output circuit paths. A corresponding number of control transistors are connected in series with the output circuit paths. Each control transistor is selectively actuated in response to a control signal. A decoder circuit is configured to receive a variable control signal and generate actuation signals in response thereto to selective actuate the control transistors to pass the mirror current to an output node. At the output node, the passed mirror currents are summed to generate a variable output current. The variable current is monotonically modulated in response to the variable control signal. | 03-03-2016 |
20150381148 | DRIVER CIRCUIT WITH GATE CLAMP SUPPORTING STRESS TESTING - A generator circuit is coupled to apply a control signal the gate terminal of a power transistor driving an output node. A reference voltage is generated having a first voltage value as the reference for the control signal and having a second, higher, voltage value for use in stress testing. A clamping circuit is provided between the reference voltage and the power transistor gate to function in two modes. In one mode, the clamping circuit applies a first clamp voltage to clamp the voltage at the gate of the power transistor when the generator circuit is applying the control signal. In another mode, the clamping circuit applies a second, higher, clamp voltage to clamp the gate of the power transistor during gate stress testing. | 12-31-2015 |
20150381125 | POWER AMPLIFIER - A power amplifier includes a clamping circuit configured to provide a clamped voltage from a power supply; an amplifier pair having first inputs coupled to the clamping circuit, second inputs and an output for providing an amplified signal; and a biasing circuit coupled between the clamping circuit and the second inputs. The biasing circuit is configured to adjust input bias voltages of the amplifier pair such that the bias voltage of the output of the amplifier pair varies proportionally to a change of the power supply. | 12-31-2015 |
20150378378 | POWER CONVERTER AND METHOD FOR REGULATING LINE TRANSIENT RESPONSE OF THE POWER CONVERTER - A power converter includes an input and an output with an energy storage circuit and a power switching circuit coupled between the input and the output. A feedback circuit generates a feedback voltage which is differentially compared to a reference in an error amplifier circuit to generate an error amplification signal. A comparator circuit generates a control signal for controlling on/off of the power switching circuit based on a first comparison signal related to the error amplification signal and a second comparison signal related to a charging current of the energy storage circuit. A regulating circuit is coupled between an output of the error amplifier circuit and an input of the comparator circuit for receiving the first comparison signal, the regulating circuit is configured to couple a voltage compensation signal related to an input voltage received by the input to an output of the error amplifier, so as to reduce a variation amount of the error amplification signal when the input voltage varies. | 12-31-2015 |
20150339963 | CURRENT SLOPE CONTROL METHOD AND APPARTUS FOR POWER DRIVER CIRCUIT APPLICATION - A low side driver includes a first transistor coupled in series with a second transistor at a low side voltage node for a load. A capacitance is configured to store a voltage and a voltage buffer circuit has an input coupled to receive the voltage stored by the capacitance and an output coupled to drive a control node of the second transistor with the stored voltage. A current source supplies current through a switch to the capacitance and the input of the voltage buffer circuit. The switch is configured to be actuated by an oscillating enable signal so as to cyclically source current from the current source to the capacitance and cause a stepped increase in the stored voltage which is applied by the buffer circuit to the control node of the second transistor. | 11-26-2015 |
20150228359 | FAILURE DIAGNOSIS CIRCUIT - A failure diagnosis circuit includes a multiplexer and a controller. The multiplexer receives address signals, and selectively outputs one of the address signals to an addressable module in response to a selecting signal. The controller generates a first one of address signals and the selecting signal. A built-in self-test circuit generates the second address signal. The addressable module includes addressable components responsive to the address signal. The controller processes the output of the addressable module responsive to the address signal to make a failure diagnosis. The built-in self-test circuit performs signature analysis on the read out output of the addressable module. | 08-13-2015 |
20150214910 | OPERATIONAL TRANSCONDUCTANCE AMPLIFIER WITH INCREASED CURRENT SINKING CAPABILITY - Described herein is an electronic device. The electronic device includes a unity gain buffer having an input coupled to an input node to receive an input voltage and an output coupled to an output node. A current sink circuit operates in a sleep mode in an absence of a sink current flowing into the output node, and operates in a sinking mode to sink the sink current from the output node to a reference supply node when the sink current flows into the output node. | 07-30-2015 |
20150214902 | DEVICE AND METHOD FOR REDUCING CLIPPING IN AN AMPLIFIER - Limiting clipping in an amplifier is accomplished in the feedback loop of a class D PWM amplifier that includes an integrator coupled to an input node and configured to generate an integrated input signal such that a comparator may then generate a PWM signal for driving an amplifier output stage based on a comparison to a triangle wave signal. To this end, the amplifier also includes a threshold signal generator for generating high and low voltage thresholds based on the triangle wave signal to be used to engage compensation circuits for limiting the overall amplification. Such compensation circuits may be bipolar junction transistors that are disposed in the feedback loop of the integrator. Thus, the overall bandwidth of the amplifier itself is not affected by adding a limiter circuit aimed at reducing clipping. | 07-30-2015 |
20150185754 | TEMPERATURE AND PROCESS COMPENSATED CURRENT REFERENCE CIRCUITS - A reference current path carries a reference current. A first transistor is coupled to the reference current path. A second transistor is also coupled to the reference current path. The first and second transistors are connected in parallel to carry the reference current. The first transistor is biased by a first voltage (which is a bandgap voltage plus a threshold voltage). The second transistor is biased by a second voltage (which is a PTAT voltage plus a threshold voltage). The first and second transistors are thus biased by voltages having different and opposite temperature coefficients with a result that the temperature coefficients of the currents flowing in the first and second transistors are opposite and the reference current accordingly has a low temperature coefficient. | 07-02-2015 |
20150185747 | LDO REGULATOR WITH IMPROVED LOAD TRANSIENT PERFORMANCE FOR INTERNAL POWER SUPPLY - A voltage regulator includes a feedback regulation loop and a drive transistor configured to source current to a regulated output. A transient recovery circuit is coupled to the voltage regulator circuit and includes a first transistor coupled to source current into a control terminal of the drive transistor, wherein the source current is in addition to current sourced in response to operation of the feedback regulation loop. The first transistor is selectively actuated in response to a drop in voltage at the regulated output. The transient recovery circuit further includes a second transistor coupled to sink current from the regulated output. The sink current has a first non-zero magnitude in the quiescent operating mode of the regulator circuit. In response to an increase in voltage at the regulated output, the operation of the second transistor is modified to increase the sink current to a second, greater, non-zero magnitude. | 07-02-2015 |
20150115927 | METHOD AND APPARATUS FOR GENERATING A DIRECT CURRENT BIAS - A voltage detector operates to detect a system power supply voltage and generate a trigger signal. A control signal generator responds to the trigger signal and generates a control signal. A DC bias generator responds to the control signal by generating a DC bias. The control signal controls the DC bias to have a first value when the power supply voltage is a first voltage and have a second value when the power supply voltage is a second voltage different from the first voltage, wherein the first value is different from the second value. A dynamic DC bias is generated which can not only support a larger voltage scope, but also significantly improves signal to noise ratio. The system power supply detection may concern stop/start operation of an automobile engine. | 04-30-2015 |
20150071464 | METHODS AND CIRCUITS TO REDUCE POP NOISE IN AN AUDIO DEVICE - A class D amplifier receives and amplifies a differential analog signal which is then differentially integrated. Two pulse width modulators generate pulse signals corresponding to the differentially integrated analog signal and two power units generate output pulse signals. The outputs the power units are coupled to input terminals of integrators via a resistor feedback network. An analog output unit converts the pulse signals to an output analog signal. The differential integration circuitry implements a soft transition between mute/un-mute. In mute, the integrator output is fixed. During the soft transition, the PWM outputs change slowly from a fixed 50% duty cycle to a final value to ensure that no pop noise is present in the output as a result of mode change. | 03-12-2015 |
20150042229 | DRIVING APPARATUS FOR A LIGHT EMITTING DEVICE AND METHOD FOR THE SAME - A driving apparatus configured to drive a light emitting device includes a driving current source module operable to supply current to the light emitting device via a node during operation. A protection module coupled to the node and the driving current source module selectively injects current to the node during operation. The driving current source module is controlled based on a detection result of a voltage on the node. | 02-12-2015 |
20140327419 | CURRENT LIMITING CIRCUIT - A current limiting circuit includes a current sensing module that is configured to sense an output current of a power transistor and to generate a corresponding sensing current which is proportional to the output current. A first current limiting module coupled to the current sensing module is configured to generate a first limiting current based on the sensing current when a variation of the output current of the power transistor exceeds a first current level. A second current limiting module coupled to the current sensing module is configured to generate a second limiting current based on the sensing current when a variation of the output current of the power transistor exceeds a second current level. A converting module coupled to the first and second current limiting modules and the power transistor controls a gate voltage of the power transistor based at least on the first and second limiting currents. | 11-06-2014 |
20140285258 | SILENT START CLASS-D AMPLIFIER - A Class-D amplifier includes a pre-amplifier having an input configured to receive an amplifier reference voltage signal which is ramped at start-up at a fast rate. An integrator has a first input configured to receive an input signal from the pre-amplifier and a second input configured to receive an integrator reference voltage signal which is ramped at start-up at a slower rate. A modulator has an input coupled to an output of the integrator. The modulator generates a pulse width modulated output signal. Operation of the Class-D amplifier is controlled at start-up by applying a slow ramped signal as the integrator reference voltage signal and a fast ramped signal as the amplifier reference voltage so that the pulse width modulated output signal exhibits an increasing change in duty cycle in response to an increasing voltage of the integrator reference voltage signal, and no “pop” is introduced at start-up. | 09-25-2014 |
20140184345 | CIRCUIT AND METHOD FOR GENERATING OSCILLATING SIGNALS - An oscillator module includes a first MOS transistor and a capacitor. The capacitor is coupled between a gate and source of the first MOS transistor. The drain of the first MOS transistor receives a first bias current and generates an oscillating output signal. A switching circuit operates in response to the oscillating output signal to selective charge and discharge the capacitor. A current sourcing circuit is configured to generate the bias current. The current sourcing circuit includes a second MOS transistor which has an identical layout to the first MOS transistor and receives a second bias current. A resistor is coupled between a gate and source of the second MOS transistor. The current sourcing circuit further includes a current mirror having an input configured to receive a reference current passing through the resistor and generate the first and second bias currents. | 07-03-2014 |
20140184278 | DRIVER CIRCUIT FOR DRIVING POWER TRANSISTORS - A driver circuit for driving a power transistor includes a converter having a first transistor and a second transistor coupled in series between a supply node and a reference node. The converter is configured to receive a first signal and in response thereto generate a second signal for selectively controlling status of the power transistor. The ratio of a first leakage current of the first transistor to a second leakage current of the second transistor is used in the generation of the second signal which is applied to the control terminal of a transistor switch that is selectively actuated to turn off the power transistor. | 07-03-2014 |
20130314159 | OPERATIONAL TRANSCONDUCTANCE AMPLIFIER WITH INCREASED CURRENT SINKING CAPABILITY - An amplifier circuit includes an input terminal and an output terminal. A current sinking transistor includes a first conduction terminal coupled to the output terminal and a second conduction terminal coupled to a reference supply node. A voltage sensing circuit has a first input coupled to the input terminal and a second input coupled to the output terminal. An output of the voltage sensing circuit is coupled to the control terminal of the current sinking transistor. The voltage sensing circuit functions to sense a rise in the voltage at the output terminal which exceeds the voltage at the input terminal, and respond thereto by activating the current sinking transistor. | 11-28-2013 |
20130313993 | VOLTAGE SLOPE CONTROL METHOD AND APPARATUS FOR POWER DRIVER CIRCUIT APPLICATION - A drive circuit includes a first transistor coupled in series with a second transistor at a first intermediate node coupled to a load. An amplifier has an output driving a control terminal of the second transistor. The amplifier includes a first input coupled to a second intermediate node and a second input coupled to a reference voltage. A feedback circuit is coupled between the first intermediate node and the second intermediate node. A slope control circuit is coupled the second intermediate node. The slope control circuit injects a selected value of current into the second intermediate node, that current operating to control the output of the amplifier in setting a slope for change in voltage at the first intermediate node. | 11-28-2013 |
20130300394 | CURRENT SLOPE CONTROL METHOD AND APPARATUS FOR POWER DRIVER CIRCUIT APPLICATION - A low side driver includes a first transistor coupled in series with a second transistor at a low side voltage node for a load. A capacitance is configured to store a voltage and a voltage buffer circuit has an input coupled to receive the voltage stored by the capacitance and an output coupled to drive a control node of the second transistor with the stored voltage. A current source supplies current through a switch to the capacitance and the input of the voltage buffer circuit. The switch is configured to be actuated by an oscillating enable signal so as to cyclically source current from the current source to the capacitance and cause a stepped increase in the stored voltage which is applied by the buffer circuit to the control node of the second transistor. | 11-14-2013 |
20130188793 | EMBEDDED SPEAKER PROTECTION FOR AUTOMOTIVE AUDIO POWER AMPLIFIER - A method of operating a speaker system including a speaker coupled to an amplifier, and a dedicated digital speaker protection circuit includes turning on the amplifier in a mute mode, after a first delay period, issuing a play command to the amplifier to place the amplifier in a play mode, but without an input signal during a second delay period, and performing a speaker offset detection during the second delay period, wherein, if there is an offset, then the amplifier is forced back into the mute mode, and if there is no offset, then the amplifier is allowed to continue to operate in the play mode. The method also includes issuing a speaker protection control signal or command if an offset is detected. | 07-25-2013 |
20130187681 | ANALOG SIGNAL SOFT SWITCHING CONTROL WITH PRECISE CURRENT STEERING GENERATOR - A switching circuit includes a first input stage having an input for receiving a first input signal, an output, and a power terminal for receiving an increasing analog current, a second input stage having an input for receiving a second input signal, an output, and a power terminal for receiving a decreasing analog current, and an output node coupled to the outputs of the first input stage and the second input stage for providing a switched output signal. An output stage is coupled between the first and second input stages and the output node. The first and second input stages are operational amplifiers. | 07-25-2013 |
20130169610 | DRIVING CIRCUIT AND DISPLAY DEVICE - A driving circuit includes a controller, a converter and a feedback module. The controller receives an input supply at a supply node, and generates a control signal according to the input supply. The converter receive an input signal at an input node and a control signal at a control node, and is configured to convert the input signal to a driving signal in response to the control signal. The driving signal of the converter is feedback by the feedback module to the controller. The input supply is generated from the input signal or the feedback driving signal. The drive circuit may drive a display device. | 07-04-2013 |
20130169362 | INPUT CLAMPING STRUCTURE FOR SOUND QUALITY IMPROVEMENT IN CAR-RADIO CLASS-AB POWER AMPLIFIER DESIGN - A clamping circuit for a class AB amplifier includes a reference voltage circuit, four NPN Darlington transistors having inputs coupled to the reference voltage circuit, and outputs for providing four clamped voltages, and a split NPN Darlington transistor having an input coupled to the reference voltage circuit, and four separate outputs for providing four AC ground voltages. | 07-04-2013 |
20130169318 | GATE-STRESS TEST CIRCUIT WITHOUT TEST PAD - A high side driver circuit includes a driver stage having an input, an output, a first power terminal and a second power terminal, a transistor having a first power terminal, a second power terminal, and a control terminal coupled to the output of the driver stage, and a switch coupled between the second power terminal of the driver stage and the second power terminal of the transistor. | 07-04-2013 |
20130169248 | SYSTEM AND METHOD FOR CONTROLLING DCM-CCM OSCILLATION IN A CURRENT-CONTROLLED SWITCHING MODE POWER SUPPLY CONVERTER - A constant-frequency current-mode-controlled boost converter circuit provides slope compensation of an inductor current, reduces reverse inductor current in light output load conditions, and reduces oscillation between a discontinuous current mode and a continuous current mode by enabling or disabling an inductor current threshold. The constant-frequency current-mode-controlled boost converter circuit is efficient and stable in light, medium, and heavy output load conditions. | 07-04-2013 |
20130169188 | BIDIRECTIONAL VOLTAGE DIFFERENTIATOR CIRCUIT - A bidirectional voltage differentiator circuit comprises start-up circuitry, sensing circuitry, and output circuitry coupled to logic circuitry. The start-up circuitry acts to start-up the sensing circuitry when the circuit is powered on, and accelerates the response of the sensing circuitry thereafter. The sensing circuitry senses variation in an input voltage applied to an input node. Responsive to the voltage variation sensed by the sensing circuitry, the output circuitry produces a state change at a first or second output node. The logic circuitry receives the states of the output nodes and produces a logic output signal to indicate the occurrence of the variation sensed in the input voltage. The voltage sensing circuit is operable to sense variation of the input voltage regardless of whether the voltage is rising or falling and without regard to the DC value of the input voltage. | 07-04-2013 |
20130141152 | VOLTAGE CONTROLLED VARIABLE RESISTOR SUITABLE FOR LARGE SCALE SIGNAL APPLICATION - A voltage controlled variable resistor circuit is configured to variably attenuate a variable source signal. A fixed attenuation circuit is coupled to receive the variable source signal and output an attenuated variable source signal. The variable source signal is further applied across a variable resistive divider formed of a fixed resistive circuit and a variable resistive circuit. The variable resistive circuit has a first input configured to receive the attenuated variable source signal and a second input configured to receive a variable resistance control signal. The variable resistive circuit is configured to have a resistance which is variable in response to the attenuated variable source signal and the variable resistance control signal. | 06-06-2013 |
20130093326 | DEVICE AND METHOD FOR DETECTING A SHORT-CIRCUIT DURING A START-UP ROUTINE - A device and method for detecting a short circuit in an electrical component during a start-up routine. In an embodiment, a device may have a problematic display having a short circuit that may result in damage to other components of the device if the device were allowed to fully startup during a normal start-up routine. Thus, power supplied to the panel may be initiated in stages so as to monitor any current that may be flowing through the panel, which in turn, may be indicative of a short circuit in the panel. If enough “leakage” current is detected through the panel during this staged startup routine, then a short-circuit detection circuit may interrupt the startup routine and lock out the operation of the device until the detected short circuit in the panel can be addressed. | 04-18-2013 |
20130077421 | FAILURE DIAGNOSIS CIRCUIT - A failure diagnosis circuit includes a multiplexer and a controller. The multiplexer receives address signals, and selectively outputs one of the address signals to an addressable module in response to a selecting signal. The controller generates a first one of address signals and the selecting signal. A built-in self-test circuit generates the second address signal. The addressable module includes addressable components responsive to the address signal. The controller processes the output of the addressable module responsive to the address signal to make a failure diagnosis. The built-in self-test circuit performs signature analysis on the read out output of the addressable module. | 03-28-2013 |
20130069721 | AMPLIFYING CIRCUIT - A circuit includes a first circuit module with a first input node, a second input node and an output node. The first circuit module receives an input signal at the first input node and generates an amplified signal at the output node. The circuit further includes a second circuit module coupled between the output node and a reference potential line. The second circuit selectively draws a current from the output node in response to a first control signal. The first control signal is generated in response to sensing a voltage fluctuation at a power supply node which supplies power to the first circuit module. | 03-21-2013 |
20130003888 | HALF OPEN-LOOP-CONTROLLED LIN TRANSMITTER - An LIN transmitter includes a current mirror coupled to a transmit output node and a control circuit coupled to a transmit input node for controlling the current mirror with various load current control signals. | 01-03-2013 |
20130003805 | LIN RECEIVER PROVIDING IMMUNITY AGAINST ISO PULSES - A LIN receiver circuit includes filtering circuitry receiving an input signal and producing a filtered signal, a first comparator comparing the filtered signal to a threshold voltage, and a driver block producing the receiver output signal. The receiver circuit further includes an input comparator, signal-adjusting circuitry, and deglitching circuitry. The input comparator detects a low voltage on the input signal, and the signal-adjusting circuitry drives the filtered signal to a particular value to shorten the length of a glitch at the output of the first comparator. Meanwhile, the deglitching circuitry detects and removes the glitch to produce a deglitcher output signal. The deglitcher output signal is received by the driver block, which outputs the receiver output signal, wherein the receiver output signal contains no glitches, and is delayed by no more than 7.5 μs, thus providing immunity to ISO pulses. | 01-03-2013 |
20130002224 | HIGH EFFICIENCY BOOST CONVERTER - A boost converter circuit receives an input power supply voltage and produces an output boosted supply voltage. The circuit includes a voltage regulator, boosting circuitry, and a timing controller. The voltage regulator provides a regulated voltage to the boosting circuitry, which controls switching a transistor to drive the output boosted supply voltage; and the timing controller controls switching the boost circuit from the start-up mode to the normal operation mode. In start-up mode, the regulated voltage is generated from the input power supply voltage. During normal operation mode, the regulated voltage is generated from the output boosted supply voltage. The circuitry performs a low-power start-up when the input power supply voltage is low, and maintains efficient low-power operation by driving the transistor to produce the output boosted supply voltage as the input power supply voltage decreases. | 01-03-2013 |
20120313615 | Summation Circuit in DC-DC Converter - An integrated circuit includes a saw-tooth generator including a saw tooth node configured to have a saw-tooth voltage generated thereon; and a first switch having a first end connected to the saw tooth node. The integrated circuit further includes a second switch coupled between an output node and an electrical ground, wherein the first switch and the second switch are configured to operate synchronously. A first current source is connected to the saw tooth node. A second current source is connected to the output node. | 12-13-2012 |
20120286831 | CIRCUIT AND METHOD FOR GENERATING A CLOCK SIGNAL - A circuit comprises a frequency divider coupled to receive an oscillating signal generated by an oscillator and a division ratio and configured to divide the oscillating signal by the division ratio into a clock signal; a temperature compensation circuit configured to measure a temperature of the oscillator and generate a division ratio to be provided to the frequency divider and a first value on the basis of the measured temperature; and a control system configured to control connection between a calibration element and the oscillator based on the first value and the oscillating signal of the oscillator. | 11-15-2012 |
20120280960 | CIRCUIT FOR USE WITH DISPLAY DEVICES AND POWER SUPPLYING METHOD - An embodiment is a circuit for use with a display device, the circuit including: a first input node configured to be operatively coupled to a first port of a data source device that provides the display device with data, to receive a first direct voltage used for a real-time display of the data on the display device; and at least one output node, configured to operatively provide the display device with at least one output voltage generated based on the first direct voltage, wherein the first port is isolated from a data port used to transmit the data. | 11-08-2012 |
20120170864 | PERCEPTUAL BLOCK MASKING ESTIMATION SYSTEM - Systems and methods are disclosed for determining the perceptibility of noise in a block of images and/or video. The systems and methods may compute a mask value for the block using a block masking generator. The mask value may indicate the perceptibility of noise in the block. The mask value may be computed using a normalized activity value and/or a texture value for the block. The normalized activity value may indicate the relative activity in the block as compared to the activity in the image and/or video. The texture value may indicate the strength and/or number of edges in the block. | 07-05-2012 |
20120169421 | AUDIO AMPLIFYING CIRCUIT WITH IMPROVED NOISE PERFORMANCE - An amplifying circuit includes a first circuit component configured to receive and amplify first and second input voltages to generate an output voltage. The first circuit component is formed by a first amplifier and a second amplifier. A second circuit component is configured to provide a first offset current that is associated with a first input current of the first amplifier. The first offset current compensates for variation in the first input current. A third circuit component is configured to provide a second offset current that is associated with a second input current of the second amplifier. The second offset current compensates for variation in the second input current. | 07-05-2012 |
20120169420 | CIRCUIT AND METHOD FOR AMPLIFYING A DIGITAL SIGNAL - An amplifier circuit includes an amplifier unit that is configured to receive an input signal and generate a switching output signal. A level shifter is configured to shift the amplitude of the input signal to have a shifted amplitude that is proportional to a peak-to-peak amplitude of the switching output signal. | 07-05-2012 |
20120169323 | CONGRUENT POWER AND TIMING SIGNALS FOR DEVICE - Congruent power and timing signals in a single electronic device. In an embodiment, a circuit may include just one isolation transformer operable to generate a power signal and a timing signal. On the secondary side, two branches may extract both a power signal and a clock signal for use in the circuit on the isolated secondary side. The first branch may be coupled to the transformer and operable to manipulate the signal into a power signal, such as a 5V DC signal. Likewise, the second circuit branch is operable to manipulate the signal into a clock signal, such as a 5 V signal with a frequency of 1 MHz. By extracting both a power supply signal and a clock signal from the same isolation transformer on the secondary side, valuable space may be saved on an integrated circuit device with only having a single winding for a single isolation transformer. | 07-05-2012 |
20120169309 | CIRCUIT AND METHOD FOR SHORT CIRCUIT PROTECTION - A boost converter includes an input terminal and an output terminal. A first switch is connected between a first intermediate node and a reference potential node. An inductive component is connected between the input terminal and the first intermediate node. A rectifying component is connected between the first intermediate node and a second intermediate node. A multi-state module is connected between the second intermediate node and the output terminal, and has at least a low resistance state and a high resistance state. A control module is coupled to the output terminal, the first switch and the multi-state module, and is operable in response to an output voltage to control the first switch and the multi-state module so that the first switch is open and the multi-state module is in the high resistance state if the output voltage is lower than a threshold value. | 07-05-2012 |
20120133284 | SYSTEM FOR REPROGRAMMING POWER PARAMETERS FOR LIGHT EMITTING DIODES - According to an embodiment of the present disclosure, a plurality of light-emitting diode (LED) modules in series are monitored. When an LED module is detected as failing or operating inadequately, a bypass switch removes the particular LED module from the series and the voltage provided to the series is modified. When the LED modules are detected as having too high of a temperature, the current provided to the LED modules is limited. | 05-31-2012 |
20110156821 | CIRCUIT AND METHOD FOR GENERATING A CLOCK SIGNAL - A circuit comprises a frequency divider configured to receive an oscillating signal generated by an oscillator and to divide the oscillating signal into a clock signal, wherein the division ratio of the frequency divider is set to a value equal to one of: the integer part of the resonant frequency of the oscillator and the integer part of the resonant frequency of the oscillator plus 1. | 06-30-2011 |
20110156774 | CIRCUIT AND METHOD FOR GENERATING A CLOCK SIGNAL - A circuit comprises a frequency divider coupled to receive an oscillating signal generated by an oscillator and a division ratio and configured to divide the oscillating signal by the division ratio into a clock signal; a temperature compensation circuit configured to measure a temperature of the oscillator and generate a division ratio to be provided to the frequency divider and a first value on the basis of the measured temperature; and a control system configured to control connection between a calibration element and the oscillator based on the first value and the oscillating signal of the oscillator. | 06-30-2011 |
20110156688 | Regulator Over-Voltage Protection Circuit with Reduced Standby Current - An embodiment of the invention relates to a power converter formed with an error amplifier and a related method. In an embodiment, a first switch is coupled in series with an error amplifier compensation capacitor. Upon detection of a current level greater than a threshold level, the compensation capacitor is decoupled from the error amplifier by opening the first switch. In an embodiment, a second switch is coupled in parallel with the compensation capacitor, and the current-sensing circuit enables conductivity of the second switch to discharge the compensation capacitor upon detection of the current level greater than the threshold level. The second switch is opened upon detection of the current level less than the threshold level. In an embodiment, the current-sensing circuit controls an output current of the power converter at a current-limit level upon detection of the internal current level greater than the threshold level. | 06-30-2011 |
20110156683 | Current mode buck-boost DC-DC controller - A current mode DC-DC controller operates with high efficiency even when the input and output voltages are close. Switches selectively connecting an input, ground and an output to inductor terminals are controlled in a buck/boost region to alternate between operation as a buck converter and operation as a boost converter. The number of switches repeatedly changing state is thus reduced, lowering switching losses and improving conversion efficiency. Current through the inductor during operation is sensed and compared to an error value to control switching from buck mode operation to boost mode operation and back. | 06-30-2011 |
20110156676 | GENERATING A REGULATED SIGNAL FROM ANOTHER REGULATED SIGNAL - An embodiment of a method includes generating a regulated output signal from a regulated intermediate signal in response to a reference signal and the regulated output signal, and generating the regulated intermediate signal from an input signal in response to the regulated output signal and the regulated intermediate signal. By generating one regulated signal (e.g., a regulated output voltage) from another regulated signal (e.g., a regulated intermediate voltage), one may significantly reduce the magnitude of the ripple component of the one regulated signal as compared to a conventional regulation technique. Furthermore, by generating the regulated intermediate signal in response to the regulated output signal, one may significantly increase the efficiency of the regulation as compared to conventional signal regulation. | 06-30-2011 |
20110154911 | FLOW METER - A flow meter for measurement of a metered fluid has a sensor element that receives a flow input of a metered fluid and outputs a flow output of the metered fluid, and a battery element. The sensor element has an inductor element and a magnetic element coupled to the inductor element. In response to movement of the magnetic element relative to the inductor element caused by a fluid pressure differential of the metered fluid, the inductive value of the inductor element changes. | 06-30-2011 |
20110148471 | Temperature-Independent Undervoltage Detector and Related Method - Embodiments related to an undervoltage detector are described and depicted. An undervoltage detector is formed to detect a low input bias voltage with a voltage divider network including first and second series circuits of semiconductor devices coupled to terminals of the input bias voltage source, and a resistor voltage divider including first and second voltage divider resistors coupled in series with the first and second series circuits. A ratio representing the numbers of semiconductor devices in the series circuits is substantially equal to a ratio of resistances in the resistor voltage divider. The equality of the ratios may be corrected by the presence of other resistances in the undervoltage detector. The semiconductor devices are each coupled in a diode configuration. The first series circuit is coupled to a current mirror to provide a bias current for a comparator that produces an output signal for the undervoltage detector. | 06-23-2011 |
20110145674 | High-efficiency dynamic transmission that has a high speed and reliability - A system and method for error correction coding is configured to dynamically implement one of a number of error correction coding methods during a transmission of data. The error correction coding method is selected based on a measured bit error rate during the transmission of data. The implementation of the error correction coding method is performed without interrupting the data transmission. | 06-16-2011 |
20110142165 | Flexible self-adaptive differential system to improve transmission efficiency - A system and method for transmitting data. The system and method is configured to dynamically implement one of a differential signaling method or a single-ended signaling method during a transmission of data. The signaling method is selected based on a measured interference level during the transmission of data. The implementation of the signaling method is performed without interrupting the data transmission. | 06-16-2011 |
20110109352 | Summation Circuit in DC-DC Converter - An integrated circuit includes a saw-tooth generator including a saw tooth node configured to have a saw-tooth voltage generated thereon; and a first switch having a first end connected to the saw tooth node. The integrated circuit further includes a second switch coupled between an output node and an electrical ground, wherein the first switch and the second switch are configured to operate synchronously. A first current source is connected to the saw tooth node. A second current source is connected to the output node. | 05-12-2011 |
20110109296 | Voltage Regulator Architecture - An integrated circuit includes a bandgap reference generator and a voltage regulator. The bandgap reference generator includes a first current path, and a first bipolar transistor with an emitter-collector path in the first current path. The voltage regulator includes a second current path, wherein the second current path mirrors the first current path; a resistor configured to receive a current of the second current path; a second bipolar transistor with a base and a collector of the second bipolar transistor being interconnected; and a third bipolar transistor connected in series with the second bipolar transistor and the resistor. A base and a collector of the third bipolar transistor are interconnected. | 05-12-2011 |
20110089923 | Accurate Current Sensing Circuit with Ultra Low Voltage Supply - An integrated circuit includes a DC-DC converter, which includes an inductor; a first transistor coupled to the inductor and configured to pass an inductor current to the inductor; and a second transistor forming a current mirror with the first transistor. The integrated circuit further includes an operational amplifier. The operational amplifier includes a first input node and a second input node. The first input node is configured to couple to a drain of the first transistor when the first transistor is turned on, and decoupled from the drain of the first transistor when the first transistor is turned off. The second input node is coupled to a drain of the second transistor. | 04-21-2011 |
20110074511 | LAYOUT AND PAD FLOOR PLAN OF POWER TRANSISTOR FOR GOOD PERFORMANCE OF SPU AND STOG - A power transistor for use in an audio application is laid out to minimize hot spots. Hot spots are created by non-uniform power dissipation or overly concentrated current densities. The source and drain pads are disposed relative to each other to facilitate uniform power dissipation. Interleaving metal fingers and upper metal layers are connected directly to lower metal layers in the absence of vias to improve current density distribution. This layout improves some fail detection tests by 17%. | 03-31-2011 |
20110074481 | NEGATIVE CHARGE PUMP WITH CURRENT PROTECTION - A charge pump circuit includes a first power transistor selectively actuated by a first control signal to deliver relatively higher amounts of current to a capacitor and a second non-power transistor connected in parallel with the first power transistor and selectively actuated by a second control signal to deliver relatively lower amounts of current to the capacitor. The charge pump circuit includes a pumped voltage output that is sensed to generate a sensed voltage output. A comparison circuit compares the sensed voltage output to a threshold voltage. A logic circuit receives an output of the comparison circuit and enables the first power transistor and disables the second non-power transistor in a first mode of operation if the comparison is not satisfied. The logic circuit further disables the first power transistor and enables the second non-power transistor in a second mode of operation if the comparison is satisfied. The logic circuit returns from the second mode of operation to the first mode of operation after the comparison is subsequently not satisfied. | 03-31-2011 |
20100123508 | SMOOTH SWITCHING BETWEEN ANALOG INPUT SIGNALS - A first switching circuit has an input for receiving a first input signal, and a second switching circuit has an input for receiving a second input signal. A node is connected to receive outputs from both the first and second switching circuits. A filter receives an unfiltered signal from the node to generate an output signal. A circuit is provided to alternately actuate the first and second switching circuits during a transition time period so as to smoothly transition the output of the filter between the first and second input signals. At least one of the first and second input signals is a time-varying analog signal. The smooth transition between the first and second input signals has a shape determined by pulse width and frequency characteristics of pulses output by the circuit to alternately actuate the first and second switching circuits. The shape may include a linear ramp, an S-shaped curve, a parabolic curve and a hyperbolic curve. | 05-20-2010 |
20090322428 | TUNABLE LINEAR OPERATIONAL TRANSCONDUCTANCE AMPLIFIER - A tunable, linear operational transconductance amplifier includes a differential voltage to current conversion unit adapted to generate first and second output signals at respective first and second output nodes responsive to first and second differential input signals. A first current amplification unit is adapted to generate a third output signal responsive to the first output signal and first and second control signals. A second current amplification unit is adapted to generate a fourth output signal responsive to the second output signal and the first and second control signals. | 12-31-2009 |