Patent application number | Description | Published |
20080258651 | METHOD AND SYSTEM FOR OPEN LAMP PROTECTION - A detector circuit monitors the phase relationship between the lamp voltage and the excitation voltage, and if one or more conditions are met, triggers the open lamp protection process in a discharge lamp system. The detection circuit can be incorporated into a lamp voltage feedback circuit and implemented on the integrated circuit level with less cost and circuit complexity. | 10-23-2008 |
20090045873 | CLOSE-LOOP CLASS-D AUDIO AMPLIFIER AND CONTROL METHOD THEREOF - The present invention discloses a Class-D power amplifier and control method thereof. In one embodiment, the amplifier feeds back the signal at the output node to the inverting input of the comparator, and provides a high frequency triangular wave signal to the non-inverting input of the comparator. In addition, the non-inverting input of the comparator may be coupled to an offset voltage, while the inverting input of the comparator may be coupled to a fixed-frequency rectangular wave signal, a feedback signal which is derived from the output stage and an input signal. In use, the switching frequency may be at least substantially fixed, so as to reduce the influence on the system caused by electromagnetic interruption (EMI). Further, the control circuit is simple, and some devices can be integrated. | 02-19-2009 |
20090140655 | SIMPLE PROTECTION CIRCUIT AND ADAPTIVE FREQUENCY SWEEPING METHOD FOR CCFL INVERTER - A CCFL inverter circuit integrates a feedback circuit and protection circuit together. For both in-phase and out-of-phase applications, sensed lamp voltages can be used for open lamp and short lamp detection and sensed currents can be used for open lamp detection. The driving circuit adjusts the open lamp frequency by using a duty cycle control signal so that the driving circuit can always achieve the desired lamp voltage gain. | 06-04-2009 |
20090273951 | SMART DRIVING METHOD FOR SYNCHRONOUS RECTIFIER AND ITS APPARATUS THEREOF - The present invention discloses a smart driving method for a secondary synchronous rectifier of an isolated converter and its apparatus thereof. The apparatus comprises: a main circuit having a secondary synchronous rectifier Q | 11-05-2009 |
20090284163 | METHOD AND APPARATUS FOR DRIVING MULTIPLE PARALLEL DISCHARGE LAMPS - The present invention provides a method and apparatus for driving multiple parallel discharge lamps, which increases the switching frequency once the open lamp condition is detected to provide an output voltage that is high enough to ignite the lamp again. | 11-19-2009 |
20090295445 | DOUBLE-EDGE PWM CONTROLLER AND ITS CONTROL METHOD THEREOF - The present invention discloses a double-edge pulse width modulation (PWM) controller based on the output current and output voltage which is modulated in real time by the output current and the output voltage. The controller uses an extra first adder to sum up the compensation signal and a triangular signal (or a saw-tooth signal); a second adder to sum up the output current signal to a bias value; a PWM comparator, with its non-inverting input receiving the output of said first adder, its inverting input receiving the output of said second adder and outputs the PWM signal. | 12-03-2009 |
20100045110 | POWER CONVERTERS AND ASSOCIATED METHODS OF CONTROL - SIMO power converters and associated methods of control are disclosed herein. In one embodiment, a method of converting a signal input signal into multiple output signals includes supplying power to a plurality of output terminals based on a signal input signal, detecting a voltage at individual output terminals, determining an arithmetic relationship between the detected voltages of the output terminals, and adjusting the power supplied to the plurality of output terminals based at least in part on the determined arithmetic relationship between the detected voltages of the output terminals. | 02-25-2010 |
20100072906 | METHODS AND APPARATUS FOR DRIVING DISCHARGE LAMPS - Methods and apparatus for driving discharge lamps are disclosed herein. In one embodiment, a method for driving a discharge lamp includes generating a switching signal to drive a discharge lamp, monitoring a working status of the discharge lamp, and determining whether the discharge lamp is operating abnormally based at least in part on the monitored working status. The method also includes decreasing a duty cycle of the switching signal when the discharge lamp is determined to operate abnormally. | 03-25-2010 |
20100117555 | PULSE DIMMING CIRCUIT AND THE METHOD THEREOF - The present invention provides a pulse dimming circuit and a method thereof. The pulse dimming circuit is compatible for both DC input signal and PWM input signal using only one circuit board. | 05-13-2010 |
20100141149 | FAULT PROTECTION METHODS AND APPARATUS FOR COLD CATHODE FLUORESCENT LAMPS - The present disclosure provides methods and apparatus for fault protection for electronic devices (e.g., cold cathode fluorescent lamps). In one embodiment, a fault signal is detected and compared with a threshold to output a comparison signal. The comparison signal is then processed to generate a trigger signal, which triggers a fault control block once it satisfies certain fault conditions. | 06-10-2010 |
20100201335 | OFF TIME CONTROL METHOD FOR SWITCHING REGULATOR - The present invention provides an off time control method and switching regulator using it. The current flowing through a switch is compared with a current threshold, and the switch is turned off if the current flowing through the switch is larger than the current threshold. The off time of the switch is determined by the load. The current threshold is variable at light load to prevent generating the audible noise and improve the whole efficiency. | 08-12-2010 |
20100259180 | LED CIRCUIT AND METHOD FOR CONTROLLING THE AVERAGE CURRENT OF THE LED - An LED circuit is disclosed. The circuit senses the average current flowing through the LED. The sensed signal is compensated and modulated. The modulated signal is then used to control the ON/OFF state of a switch that supplies power to the LED. | 10-14-2010 |
20100264985 | CLOSE-LOOP CLASS-D AUDIO AMPLIFIER AND CONTROL METHOD THEREOF - The present invention discloses a Class-D power amplifier and control method thereof. In one embodiment, the amplifier feeds back the signal at the output node to the inverting input of the comparator, and provides a high frequency triangular wave signal to the non-inverting input of the comparator. In addition, the non-inverting input of the comparator may be coupled to an offset voltage, while the inverting input of the comparator may be coupled to a fixed-frequency rectangular wave signal, a feedback signal which is derived from the output stage and an input signal. In use, the switching frequency may be at least substantially fixed, so as to reduce the influence on the system caused by electromagnetic interruption (EMI). Further, the control circuit is simple, and some devices can be integrated. | 10-21-2010 |
20100265742 | SWITCHING REGULATOR WITH FREQUENCY LIMITATION AND METHOD THEREOF - The present invention provides a switching regulator with frequency limitation and method thereof. The switching frequency of the switching regulator is limited through setting of a minimum off time, so as to improve the efficiency and EMI distribution of the switching regulator. | 10-21-2010 |
20100270937 | CIRCUIT AND METHOD FOR STRIKING CCFL - A circuit for controlling the switch frequency of an inverter that strikes and drives fluorescent lamps is disclosed. The circuit comprises a frequency generator and an offset circuit. The offset circuit provides a current signal in response to the lamp status. The frequency generator provides a frequency control signal in respond to the current signal so as to control the switch frequency of the inverter. When the lamp is open, the switch frequency of the inverter is higher; when the lamp is lighted, the switch frequency of the inverter is lower. | 10-28-2010 |
20100302288 | DUAL ENDED DRIVER CIRCUIT FOR LCD BACKLIGHT AND THE METHOD THEREOF - A dual ended driver circuit for a LCD backlight is disclosed. The circuit comprises a master board and a slave board, which provides a first output drive signal and a second output drive signal to either end of a lamp set, respectively. The circuit only uses one control chip to synchronize and make symmetrical the first output drive signal and the second output drive signal. | 12-02-2010 |
20100302815 | SWITCHING MODE POWER SUPPLY WITH A MULTI-MODE CONTROLLER - A switching mode power supply with a multi-mode controller is provided. The switching mode power supply may include a transformer having a primary winding and a secondary winding to supply power to a load. A feedback circuit may be included to generate a feedback signal that varies in relation to the load on the secondary winding. The multi-mode controller may include a switching circuit, a frequency control circuit and a current limiting circuit. The switching circuit may be coupled to the primary winding to control current flow through the primary winding. The frequency control circuit may control a switching frequency of the switching circuit based on the feedback signal. The current limiting circuit may limit current flow through the primary winding by causing the switching circuit to suspend current flow through the primary winding when the current reaches a peak current limit that is set based on the feedback signal. | 12-02-2010 |
20100302816 | SWITCHING MODE POWER SUPPLY WITH A SPECTRUM SHAPING CIRCUIT - In accordance with the teachings described herein, systems and methods are provided for a switching mode power supply. In one example, the switching mode power supply may include a transformer, a switching circuit and a switching control circuit. The transformer receives a DC input voltage on a primary winding and generates a DC output voltage on a secondary winding. The switching circuit, which may include a MOSFET switch, is coupled to the transformer and is configured to switch the transformer on and off. The switching control circuit generates a switching control signal to control the switching circuit in order to regulate the DC output voltage of the transformer. The switching control circuit is configured to generate the switching control signal as a function of a timing signal having a varying frequency, wherein the varying frequency of the timing signal causes a switching frequency of the switching circuit to vary over a period of time in order to reduce electromagnetic interference caused by the switching circuit. | 12-02-2010 |
20110002068 | SWITCHING REGULATOR WITH FAULT PROTECTION AND METHOD THEREOF - A switching regulator with fault protection and method thereof. The switching regulator comprises a switching circuit, a control circuit, a fault detection circuit and a fault timer. The fault detection circuit is electrically coupled to the switching circuit to detect whether a fault condition exists and generate a fault signal accordingly. The fault timer starts to time once the fault signal becomes valid, and is reset when the fault signal becomes invalid. If the fault time reaches a first time threshold, the control circuit is disabled, and the switch in the switching circuit is turned off. | 01-06-2011 |
20110006706 | LATCH-OFF OF REAL TIME SYNCHRONOUS RECTIFICATION FOR LIGHT LOAD CONTROL - The present invention discloses a light load control circuit and the method accordingly where the synchronous rectification is latched off selectively according to the gate voltage of the synchronous rectifier. | 01-13-2011 |
20110012538 | LATCH-OFF OF SYNCHRONOUS RECTIFICATION FOR LIGHT LOAD CONTROL - Disclosed is a light load control circuit and the method accordingly where the synchronous rectification is latched off when the light load condition is detected for several successive cycles. | 01-20-2011 |
20110062894 | COLD CATHODE FLUORESCENT LAMP DRIVING CIRCUITS AND ASSOCIATED METHODS OF CONTROL - Methods and circuits for CCFL driving circuit control are disclosed according to various embodiments of the present disclosure. In certain embodiments, the methods and circuits for CCFL driving circuit control provide a control signal for regulating both the duty ratio and frequency of the switching control signal that controls the CCFL driving circuit. External components for control loop compensation and frequency sweeping rate, and/or striking frequency setting may also be utilized. | 03-17-2011 |
20110084677 | POWER SUPPLIES AND ASSOCIATED METHODS OF CONTROL - Switching mode power supplies (SMPS) that can operate in a control mode for a normal load condition and operate with a burst-mode controller for a light load condition are disclosed herein. In one embodiment, a method for controlling the switching mode power supply includes when the load is in a light load condition, the switching mode power supply is controlled by a burst-mode controller. | 04-14-2011 |
20110110123 | SWITCHING MODE POWER SUPPLY SPECTRUM SHAPING AND THE METHOD THEREOF - Embodiments of circuits and methods for a switching mode power supply are described in detail herein. In one embodiment, a switching mode power supply includes a transformer having a primary winding and a secondary winding to supply power to a load, a feedback circuit that generates a feedback signal that varies in relation to the load on the secondary winding, a switching circuit coupled to the primary winding to control current flow through the primary winding, and a control circuit coupled to the switching circuit to control the on/off status of switching circuit in response to the feedback signal and the current flow through the primary winding. The control circuit comprises a spectrum shaping circuit configured to generate a spectrum shaping signal in response to the feedback signal. The spectrum shaping signal can then be used to regulate the switching frequency and the spectrum shaping range. | 05-12-2011 |
20110182095 | PACKAGE FOR SYNCHRONOUS RECTIFIER MODULE - The present technology discloses a package for a synchronous rectifier module, and also discloses synchronous rectification circuits and power supply adapters. The synchronous rectification circuit co-packages the synchronous rectifier and the driver into one single package. The single package simplifies the external circuitry and reduces potential electromagnetic interferences. | 07-28-2011 |
20110199793 | SWITCHING MODE POWER SUPPLY WITH PRIMARY SIDE CONTROL - The present technology are directed to switching mode power supplies with primary side control. In one embodiment, the switching mode power supply provides an equivalent current signal which represents a load current. The equivalent current signal is then used to control a switching circuit in the switching mode power supply. | 08-18-2011 |
20110227492 | DRIVER SYSTEMS FOR DRIVING LIGHT EMITTING DIODES AND ASSOCIATED DRIVING METHODS - LED driver systems and associated methods of control are disclosed herein. In one embodiment, the LED driver system comprises a converter and a controller. The controller is responsive to the LED current feedback signal and a dimming signal, and operable to generate a continuous gate drive signal to control the primary side switch of the converter. Thus, the controller regulates the output current of the converter. | 09-22-2011 |
20110227493 | LIGHT EMITTING DIODE DRIVER SYSTEMS AND ASSOCIATED METHODS OF CONTROL - Light emitting diode (LED) dimming and driver systems and associated methods of control are disclosed herein. In one embodiment, a system comprises a PFC stage and an LED driver stage. The LED driver stage comprises an isolated converter and a controller responsive to a dimming signal to dim LED strings for backlight. The controller also regulates an output current of the isolated converter. | 09-22-2011 |
20110227497 | POWER SYSTEMS FOR DRIVING LIGHT EMITTING DIODES AND ASSOCIATED METHODS OF CONTROL - Embodiments of LED driver circuits and the associated methods are disclosed herein. In one embodiment, the LED driver circuit comprises a switch-mode converter, a controller, a feedback circuit, and a gating circuit. The feedback circuit includes a current balance circuit. The gating circuit is responsive to both a current feedback signal and a voltage feedback signal and is configured to select one of them as the feedback signal. | 09-22-2011 |
20110228570 | SWITCHING MODE POWER SUPPLIES WITH PRIMARY SIDE CONTROL AND ASSOCIATED METHODS OF CONTROL - Switching mode power supplies with primary side control and associated methods of control are disclosed. In one embodiment, a signal with input voltage information and a signal with both input voltage information and output voltage information are provided to a subtracter to generate a feedback signal that is indicative of the output voltage. The feedback signal is then used to control the switching mode power supply. | 09-22-2011 |
20110234122 | CIRCUITRY FOR DRIVING LIGHT EMITTING DIODES AND ASSOCIATED METHODS - Circuitry and methods for driving a plurality of LED strings are disclosed herein. In one embodiment, the circuitry comprises a plurality of current regulating circuits electrically coupled to the LED strings and are configured to regulate a current flowing through the LED strings. At least two control circuits are coupled to the current regulating circuits and are configured to generate a control signal according to terminal voltages of the corresponding current regulating circuits. A voltage converter is electrically coupled to the LED strings and to the at least two control circuits, and is configured to regulate the DC driving voltage according to the at least two control signals. | 09-29-2011 |
20110285301 | TRIAC DIMMER COMPATIBLE SWITCHING MODE POWER SUPPLY AND METHOD THEREOF - Triac dimmer compatible switching mode power supplies used as LED drivers are disclosed herein. A PFC controller is configured in the switching mode power supplies. With the PFC controller, the current keeping the triac in the on-state is supplied by the DC/DC converter, and the LC resonance is reduced. | 11-24-2011 |
20120001603 | VOLTAGE REGULATOR WITH ADAPTIVE HYSTERETIC CONTROL - A voltage regulator with adaptive hysteretic control. The voltage regulator may include a top switch (e.g., MOSFET) configured to couple a power supply supplying an input voltage to a load. An adaptive hysteretic control circuit of the voltage regulator may turn on the top switch when the feedback voltage reaches the low threshold and turn off the top switch when the feedback voltage reaches the high threshold. The adaptive hysteretic control circuit may adjust the upper and lower threshold to make the voltage regulator working like a constant on time control circuit in steady state. When a step down transient happens, the top switch could be turned off when the output voltage reaches the upper threshold, and when a step up transient happens, the top switch could be turned on when the output voltage reaches the lower threshold, it makes the voltage regulator working like a hysteretic control circuit. | 01-05-2012 |
20120056552 | MULTI-MODE DIMMING CIRCUIT - The present disclosure discloses a multi-mode dimming circuit configurable to operate in a first dimming mode, a second dimming mode and a third dimming mode. The present disclosure also discloses separate dimming circuits for respectively realize the three dimming modes. In one embodiment the multi-mode dimming circuit may comprise a first input terminal, a second input terminal, a third input terminal, an output terminal, a resistive device, an oscillation circuit and a pulse width modulation (PWM) circuit. Users may flexibly configure the multi-mode dimming circuit to operate in one of the three different dimming modes by varying the external devices and/or signals coupled to each of the first, second and third input terminals. | 03-08-2012 |
20120112795 | Peak Current Control Circuit for Switching Mode Power Supply and Method Thereof - A switching mode power supply with improved peak current control is disclosed. A varying reference signal is adopted to limit the peak current in the energy storage component. The varying reference signal is an exponential function of a time period when a power switch is ON, wherein the power switch is coupled to the energy storage component. The varying reference signal may be generated by a circuit comprising a RC circuit and one or several voltage sources. | 05-10-2012 |
20120113684 | Compensation Circuit for Constant Current Regulation of Power Supply and Method Thereof - A compensation circuit and method for constant current regulation of switching mode power supply are disclosed. The ringing waveform of a feedback signal, indicative of the output current of the power supply, causes error. To eliminate the error, a current source charges a capacitor in response to a demagnetizing oscillation signal indicative of the error caused by the ringing waveform of the feedback signal. The voltage across the capacitor is compared to a reference signal to generate a more accurate signal indicative of the conductive time of a secondary diode in a secondary winding of the switching mode power supply. This more accurate signal is inputted to a logic circuit to generate a constant current control signal to control a power switch of the power supply. | 05-10-2012 |
20120139505 | Bridgeless PFC Converter and the Method Thereof - A bridgeless PFC (power factor correction) converter with improved efficiency is disclosed. The bridgeless PFC converter comprises: a first input terminal and a second input terminal configured to receive an input AC signal; an output terminal; an inductor set comprising N inductors, wherein a first terminal of each inductor is coupled to the first input terminal; and an output stage comprising (N+1) switching circuits coupled between the output terminal and a ground node. | 06-07-2012 |
20120248984 | BALLAST AND ASSOCIATED CONTROL CIRCUIT - The embodiments of the present invention disclose a ballast and associated control circuit wherein the control circuit comprises a multi function pin, a preheat cut-off circuit and an over-voltage protection circuit, wherein the multi function pin is coupled to the preheat cut-off circuit and a first switch configured to turn on the first switch at a preheat state of the ballast and to turn off the first switch at the end of the preheat state, and wherein the multi function pin is further coupled to the over-voltage protection circuit and a voltage sense circuit configured to receive a sensed output voltage signal and to stop the ballast after the preheat state when the sensed output voltage is larger than a first threshold. Compared with prior art, the present invention may reduce the volume and lower down the cost of circuit. | 10-04-2012 |
20120274293 | MULTIPHASE CONVERTER WITH CONTROLLABLE PHASE SHIFT - In one embodiment, a multiphase converter is disclosed. The multiphase converter may comprise a plurality of phase circuits and a plurality of phase control circuits. Each phase circuit may comprise a switch having a control terminal, and the control terminal of the switch may be configured to receive a drive signal. Each phase control circuit may be corresponding to one of the phase circuits, and each phase control circuit may be configured to provide a phase control signal to adjust an ON-time period or a reference signal for the corresponding phase circuit. The phase control signal may be responsive to the drive signal of the corresponding phase circuit. | 11-01-2012 |
20120293141 | BRIDGELESS PFC CONVERTER AND THE METHOD THEREOF - A bridgeless PFC (power factor correction) converter with improved efficiency is disclosed. The bridgeless PFC converter comprises: input terminals configured to receive an input AC power supply; an output terminal configured to provide power supply; a high frequency bridge arm comprising a first switch and a third switch coupled between the output terminal and a ground node; a low frequency bridge arm comprising a second switch and a fourth switch coupled between the output terminal and the ground node; an inductor coupled between the input AC power supply and the high frequency bridge arm; and a control circuit configured to control the switching of switches in the high frequency bridge arm and the low frequency bridge arm. | 11-22-2012 |
20120300520 | SWITCHING MODE POWER SUPPLY WITH SYNCHRONOUS RECTIFYING CONTROL CIRCUIT - A switching mode power supply comprising a synchronous rectifying control circuit. The synchronous rectifying control circuit comprising an integrating circuit, a first comparison circuit and a logic circuit. The integrating circuit is configured to provide an integrating signal. The first comparison circuit comprises a first input coupled to the output of the integrating signal, a second input configured to receive a first threshold signal, and an output. The logic circuit comprises a first input coupled to the output of the first comparison circuit and an output coupled to a control terminal of the secondary switch, and the secondary switch is configured to be turned OFF when the integrating signal is less then the first threshold signal. | 11-29-2012 |
20130020960 | POWER SUPPLY WITH CHARGE PUMP AND CONTROL METHOD THEREOF - The present invention provides a power supply comprising a driver and a charge pump. The driver is configured to provide a driving signal to a load. The charge pump comprises a first capacitor coupled to the load in parallel, at least one flying capacitor, a second capacitor and a switch array comprising a plurality of switches. The switch array is coupled to the first capacitor, the second capacitor and the at least one flying capacitor. The switch array receives the voltage across the first capacitor and controls the charge and discharge of the at least one flying capacitor, so as to make the voltage across the second capacitor be larger than the voltage across the first capacitor. | 01-24-2013 |
20130082742 | LOAD DETECTING CIRCUITS AND THE METHOD THEREOF - A no-load detecting circuit and the method thereof are disclosed. The no-load detecting circuit may be applied in switching mode power supplies or other circuits. The no-load detecting circuit comprises: a variable resistance circuit coupled in series to a load of the switching mode power supply; and a first comparison circuit coupled to the variable resistance circuit to receive the voltage across the variable resistance circuit, wherein based on the comparison of the voltage across the variable resistance circuit and a first threshold, the first comparison circuit generates a no-load detecting signal indicative of the load status; wherein the equivalent resistance of the variable resistance circuit varies based on the varying of the load of the switching mode power supply. | 04-04-2013 |
20130166947 | POWER SYSTEM WITH HOT-SWAP AND THE METHOD THEREOF - The present disclosure discloses a power system with hot-swap with a buck converter. The power system comprises a front stage, a hot-swap stage and a load stage; wherein the hot-swap stage comprises: a buck converter having a switch operate at ON/OFF state to provide a desired output voltage to the load stage with low power loss and optimized thermal design. | 06-27-2013 |
20130257399 | CONSTANT ON-TIME SWITCHING CONVERTER AND CONTROL METHOD THEREOF - A controller used in a switching converter. The switching converter includes a switching circuit having at least one switch. The controller comprises an on-time control circuit generating an on-time control signal, a slope compensation circuit generating a slope compensation signal, a comparing circuit, a logic circuit and a load detection circuit. The comparing circuit generates a comparison signal based on the slope compensation signal, a reference signal and the output voltage of the switching circuit. The logic circuit generates a control signal to control the ON and OFF switching of the at least one switch based on the on-time control signal and the comparison signal. The load detection circuit detects the load condition. The slope compensation circuit adjusts the slope compensation signal based on the load condition. | 10-03-2013 |
20130300384 | ISOLATED SWITCHING MODE POWER SUPPLY AND THE METHOD THEREOF - An isolated switching mode power supply, having: a transformer having a primary winding, a secondary winding and a third winding; a current limit comparator configured to provide a current limit signal based on the current sense signal and the peak current signal; a logic circuit configured to provide a logic control signal based on the frequency control signal and the current limit signal; a startup control circuit configured to generate a startup control signal based on the current sense signal; a load detecting circuit configured to provide a load detecting signal based on the second feedback signal and the switching signal; and a selector configured to provide the logic control signal or the startup control signal based on the load detecting signal. | 11-14-2013 |
20130301310 | ISOLATED SWITCHING MODE POWER SUPPLY AND THE METHOD THEREOF - An isolated switching mode power supply, having: an input terminal; an output terminal; a transformer having a primary winding and a secondary winding; a primary power switch coupled to the primary winding; a secondary power switch coupled between the secondary winding and the output terminal of the power supply; a secondary controller configured to generate a frequency modulation signal based on the output voltage and the first feedback signal; a coupled device configured to provide a frequency control signal based on the output voltage and the frequency modulation signal; and a primary controller configured to provide a switching signal to control the primary power switch based on the current sense signal and the frequency control signal. | 11-14-2013 |
20130301311 | SWITCHING MODE POWER SUPPLY AND THE METHOD THEREOF - A switching mode power supply, having: an input port; an output port; an energy storage component and a pair of power switches coupled between input port and the output port; an error amplifier configured to generate an amplified error signal based on the feedback signal and the reference signal; an error comparator configured to generate a frequency control signal based on the amplified error signal and the first sawtooth signal; a peak current generator configured to generate a peak current signal based on the frequency control signal; a peak current comparator configured to generate a current limit signal based on the peak current signal and the current sense signal; and a logic circuit configured to generate a switching signal to control the power switches based on the frequency control signal and the current limit signal. | 11-14-2013 |
20130307498 | MULTI-PHASE SWITCHING CONVERTER AND CONTROL METHOD THEREOF - A multi-phase switching converter comprising a plurality of switching circuits, a comparing circuit and a control circuit. The comparing circuit generates a comparison signal based on a reference signal and the output voltage of the multi-phase switching converter. The control circuit can turn on the following switching circuit based on the comparison signal only after the time from the current switching circuit being turned on reaches a first time threshold or the off-time of the current switching circuit reaches a second time threshold, wherein the first time threshold is longer than the second time threshold. | 11-21-2013 |
20130308349 | SWITCHING REGULATOR, THE CONTROL CIRCUIT AND THE METHOD THEREOF - A switching regulator that decreases power loss and resolves thermal issues by jumping its switching frequency to a maximum frequency when its load reaches a peak load. | 11-21-2013 |
20140043875 | OFF-LINE REGULATOR AND ASSOCIATED METHOD - The present invention discloses an off-line regulator. The off-line regulator comprises a rectification circuit configured to rectify an AC line voltage into a rectified line voltage; a pass device coupled between the rectified line voltage and a first capacitor, the pass device is configured to be turned ON or OFF according to a comparison signal indicating whether the rectified line voltage is over a threshold voltage. The first capacitor delivers an interim voltage into a converter which supplies power to a load. Wherein a second capacitor coupled across a driver which driving the pass device is charged by the first capacitor when the comparison signal is at a first state, and the driver is boosted when the comparison signal is at a second state. | 02-13-2014 |
20140152243 | SWITCHING CHARGER, THE CONTROL CIRCUIT AND THE CONTROL METHOD THEREOF - A switching charger having a control circuit configured to provide a control signal; a power stage turned ON and OFF by the control signal; an inductor coupled between the power stage and a load; and an output capacitor coupled in parallel with the load; a current sense circuit integrated to the control circuit to sense a current flowing through the power stage. | 06-05-2014 |
20140153301 | AC SIGNAL DETECTOR AND THE METHOD THEREOF - An AC signal detector having: a rectify circuit having a first input terminal and a second input terminal configured to receive an AC signal, and an output terminal configured to provide a rectified signal based on the AC signal; a detecting circuit having an input terminal coupled to the output terminal of the rectify circuit to receive the rectified signal, and an output terminal configured to provide a square signal based on the rectified signal; and an unplug indicate circuit having an input terminal coupled to the detecting circuit to receive the square signal, and an output terminal configured to provide an unplug indicate signal based on the square signal. | 06-05-2014 |
20140285163 | HIGHLY EFFICIENT PFC CIRCUIT AND CONTROL METHOD THEREOF - A PFC circuit includes: a switching circuit having a power switch; an on time control circuit for controlling an on time period of the power switch; a first off time control circuit; a second off time control circuit; and a logic circuit selectively controls the power switch working under CCM or DCM; when working under CCM, the first off time control circuit controls an off time period of the power switch and when working under DCM, the second off time control circuit controls the off time period of the power switch. | 09-25-2014 |
20150016154 | PEAK SAMPLE CIRCUIT FOR AC VOLTAGE AND METHOD THEREOF - A peak sample circuit for AC voltage, including: a rectifier coupled to receive an AC voltage and to rectify the AC voltage to generate a rectified signal; a delay circuit coupled to receive the rectified signal and to delay the rectified signal to generate a delayed rectified signal; a comparison circuit coupled to receive the delayed rectified signal and to generate a square signal based on the comparison of the rectified signal and the delayed rectified signal; and a sample output circuit coupled to receive the rectified signal, wherein the sample output circuit samples the rectified signal under the control of the square signal and provides a peak sample signal representative of the peak value of the AC voltage. | 01-15-2015 |