Abstract: An isolated switching converter includes a transformer having a primary winding, a secondary winding and an auxiliary winding, a primary switch coupled to the primary winding, a secondary switch coupled to the secondary winding, and a feedback circuit coupled to the auxiliary winding to generate a feedback signal indicative of the output voltage. Under normal operation, the primary switch is controlled based on the feedback signal and the secondary switch is controlled based on the status of the primary switch. Under light load condition, the secondary switch is controlled based on the output voltage. The secondary switch is turned on to generate a negative secondary current flowing through the secondary winding and turned off when the negative secondary current reaches a secondary current threshold. The primary switch is turned on based on a negative primary current and turned off when the primary current reaches a primary current threshold.

Abstract: A controller of an isolated switching converter includes an error amplifying circuit, a modulation signal generator, a first comparison circuit, a primary off detection circuit, a secondary logic circuit, an isolation circuit and a primary logic circuit. The error amplifying circuit generates a compensation signal based on the difference between a reference signal and a feedback signal. The first comparison circuit compares the compensation signal with a modulation signal generated by the modulation signal generator and generates a first comparison signal. The primary off detection circuit detects whether the primary switch is off and generates a primary off detection signal. The secondary logic circuit generates a secondary control signal to control the secondary switch based on the first comparison signal and the primary off detection signal. The isolation circuit receives the first comparison signal and generates a synchronous signal electrically isolated from the first comparison signal.

Abstract: A power converter having a current limit module and a method for controlling the power converter. The power converter converts an input voltage to an output voltage based at least on driving a main switch to switch on and off and regulates the output voltage through regulating a duty cycle of the main switch. The current limit module is configured to compensate a first current limit threshold indicative of a maximum allowable value of a peak value of a switching current of the main switch with a threshold compensation signal indicative of the duty cycle to provide a second current limit threshold. The second current limit threshold is used to limit the maximum value of the peak value, so that a maximum allowable output power of the power converter is substantially uninfluenced by the variation in the duty cycle.

Abstract: A switching mode power supply (SMPS) includes a transformer having a primary winding, a secondary winding for providing an output voltage and an auxiliary winding, a primary switch coupled to the primary winding, a secondary rectifying diode coupled to the secondary winding and a secondary switch connected in parallel with the secondary rectifying diode. A control method used in the SMPS includes: comparing a voltage across the secondary switch with a first secondary threshold and a second secondary threshold and generating a hysteresis comparison signal; timing based on the hysteresis comparison signal; comparing the voltage across the secondary switch with a third secondary threshold when the timing period reaches a first predetermined time; turning ON the secondary switch when the voltage across the secondary switch is less than a third secondary threshold; and turning on the primary switch when the conduction of the secondary switch is detected.

Abstract: The present invention discloses a LED driver including a power stage, an inductor, an error amplifier, a set comparator, a first timer, a logical AND circuit, a reset comparator, a second timer a logical OR circuit, a RS flip flop and a driving circuit. The LED driver provides sufficient latching current for the TRIAC dimmer with no large RC circuit, so as to optimize the dimming and reduce system size.

Abstract: 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; wherein the control circuit limits a current flowing through the inductor in a hysteretic window, and wherein the hysteretic window is adjusted according to an ON time of the control signal.

Abstract: A control circuit for a synchronous rectification circuit, a LLC resonant converter and a control method. The control circuit has a first comparing circuit, a second comparing circuit, a blanking circuit, a first logic circuit and a second logic circuit. The blanking circuit is configured to provide a first blanking signal and a second blanking signal to avoid one or more repeated conduction of a first synchronous rectifier and a second synchronous rectifier respectively, and the first blanking signal and the second blanking signal are logic complementary.

Abstract: A constant on-time control switching converter with DC calibration is disclosed. A current flowing into a capacitor of a DC calibration circuit is reduced by introducing a transconductance amplifier and a resistor. Thus, the equivalent capacitance of the capacitor is magnified, which allows the user to integrate a capacitor with smaller capacitance to realize DC calibration.

Abstract: A field effect transistor (“FET”), a termination structure and associated method for manufacturing. The FET has a plurality of active transistor cells and a termination structure. The termination structure for the FET includes a plurality of termination cells arranged substantially in parallel from an inner side toward an outer side of a termination area of the FET. Each of the termination cells comprises a termination trench lined with a termination insulation layer and filled with a termination conduction layer. The innermost termination cell is electrically coupled to gate regions of the active transistor cells while the rest of the termination cells are electrically floating.

Abstract: A switch-mode power supply includes a converter, a controller and a charging current. The charging current includes a logic circuit, a first current source and a second current source, to generate a charging current proportional to an input voltage of the switch-mode power supply, and also to generate a logic control signal indicative of either of two operation modes.

Abstract: A switch mode power supply having an output terminal configured to provide an output voltage, the switch mode power supply has a first switch and a control circuit, wherein the control circuit is configured to receive a current sense signal via a reuse input pin when the first switch is turned ON, and the control circuit is configured to receive a voltage sense signal via a reuse input pin when the first switch is turned OFF.

Abstract: A switching converter providing an output voltage has at least one switch and a control circuit. The control circuit has a slope compensation module, an output correction module and a control module, wherein the slope compensation module provides a slope compensation signal, the output correction module provides a voltage trim signal based on the slope compensation signal, and the control module provides a control signal to control the at least one switch based on the slope compensation signal, the voltage trim signal, a reference signal, the output voltage and an error compensation signal provided based on a difference between the output voltage and a set target of the output voltage.

Abstract: A power loss control method comprises detecting a load condition of the MOS unit, and adjusting driving loss of the MOS unit based on the load condition. The driving loss of the MOS unit is configured to decrease when the MOS unit is at light load condition.

Abstract: A LED driver system includes a LED converter converting an input voltage to an output voltage to drive a LED load via a main switch; a sensing circuit generating a feedback signal on the output terminal according to a load current through the LED load; an over-shoot detecting circuit generating an over-shoot signal according to the load current and a second reference signal; a logic circuit generating a switching signal according to a control signal and the over-shoot signal to control the main switch. The control signal is generated according to the feedback signal and a first reference signal, and the second reference signal is larger than the first reference signal.

Abstract: A switch mode power supply having an output terminal configured to provide an output voltage, the switch mode power supply has a first switch and a control circuit. The control circuit is configured to provide a switching control signal to control the first switch. The control circuit is configured to provide the switching control signal based on a first pulse signal having a first frequency and a second frequency for a light load condition, and the control circuit is configured to provide the switching control signal based on a second pulse signal for a non-light load condition.

Abstract: A charger system with a digital interface circuit, wherein the digital interface circuit has an N-bit control register, wherein N is a positive integer no less than 2, and wherein the N-bit register has a primary state machine, at a first portion of addresses of the control register, configured to instruct operation statuses of a system management bus host; and a secondary state machine, at a second portion of addresses of the control register, configured to instruct a data bit of transmission of a corresponding control instruction under each of the operation statuses of the system management bus host.

Abstract: 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.

Abstract: A single inductor multiple output buck converter includes an inductor having a first terminal and a second terminal, a first switch coupled between an input voltage and the first terminal of the inductor, a second switch coupled between the first terminal of the inductor and a reference ground, a third switch coupled between the second terminal of the inductor and a first output voltage, and a fourth switch coupled between the second terminal of the inductor and a second output voltage. A first feedback signal indicative of the first output voltage is compared with a first reference signal to generate a first comparison signal. A second feedback signal indicative of the second output voltage is compared with a second reference signal to generate a second comparison signal. Then which one of the first comparison signal and the second comparison signal is asserted first is detected, and the first to fourth switches are controlled based on the detection result.

Abstract: An LED driving apparatus includes a rectifier bridge generating a DC bus voltage, a bus capacitor coupled between the output terminal of the rectifier bridge and a reference ground, a tank element, a first transistor, a second transistor, a free-wheeling switch, an output capacitor, a voltage sensing circuit generating a voltage sensing signal indicative of the DC bus voltage, a bleeding circuit providing a bleeding current for the bus capacitor, and a bleeding control circuit generating a control signal to control the bleeding circuit based on the voltage sensing signal.

Abstract: A semiconductor device with a substrate, an epitaxy layer formed on the substrate, a plurality of deep wells formed in the epitaxy layer, a plurality of trench gate MOSFET units each of which is formed in top of the epitaxy layer between two adjacent deep well, wherein a trench gate of the trench gate MOSFET unit is shallower than half of the distance between two adjacent deep wells, which may reduce the product of on-state resistance and the gate charge of the semiconductor device.