Abstract: An efficiency tracking method of a controller applied to a flyback power converter includes before the controller soft starts, an original frequency variation curve setting voltage generated by the controller outputting an original frequency variation curve setting detection current to an original frequency variation curve setting detection resistor determining a frequency variation curve of the flyback power converter, and utilizing adjustment of resistance of the original frequency variation curve setting detection resistor to achieve efficiency optimization. Therefore, the controller controls an output voltage of the flyback power converter and tracks a maximum power point of the flyback power converter according to the efficiency tracking method to achieve efficiency optimization.

Abstract: A controller applied to a power converter is installed in a primary side of the power converter. The controller includes a capacitor, an adjustment signal generation circuit, and a discharge circuit. The capacitor is used for generating a tracking voltage. The adjustment signal generation circuit is used for generating an adjustment signal according to a feedback voltage and the tracking voltage. The discharge circuit is used for discharging the capacitor according to the feedback voltage and the adjustment signal. The tracking voltage is used for tracking a state of a magnetizing current of a magnetizing inductor of the primary side of the power converter, and when the tracking voltage consists with the state of the magnetizing current, the tracking voltage is applied to at least one of zero-voltage switching (ZVS) control and quasi-resonant (QR) control of the power converter.

Abstract: A package applied to a flyback power converter includes a first lead frame and a second lead frame. The first lead frame connects to at least one component of a primary side of the flyback power converter. An isolation distance exists between the first lead frame and the second lead frame. The primary side of the flyback power converter is galvanically isolated from and communicates with a secondary side of the flyback power converter through capacitive coupling effect between the first lead frame and the second lead frame.

Abstract: A controller applied to a primary side of an inductor-inductor-capacitor (LLC) resonant converter includes a common-mode voltage generation circuit and a control signal generation circuit. The common-mode voltage generation circuit is used for generating a common-mode voltage. The control signal generation circuit is used for generating an upper bridge switch control signal and a lower bridge switch control signal according to a compensation voltage corresponding to an output voltage of the LLC resonant converter, a sensing voltage corresponding to an input voltage of the LLC resonant converter, and the common-mode voltage, wherein the upper bridge switch control signal and the lower bridge switch control signal control an upper bridge switch and a lower bridge switch of the primary side of the LLC resonant converter, respectively.

Abstract: A secondary-side control method of a flyback power converter includes a primary controller included in the flyback power converter generating a first gate control signal to turn on a power switch at a first predetermined valley of a first voltage after the primary controller enters a start-up mode; and a secondary controller included in the flyback power converter generating a trigger pulse to a synchronous switch at a second predetermined valley of a second voltage to make the primary controller enter a secondary-side control mode from the start-up mode after the secondary controller detects a first coupling voltage corresponding to the first gate control signal on the second voltage.

Abstract: A secondary controller applied to a secondary side of a power converter includes a control signal generation circuit and a gate control signal generation circuit. The gate control signal generation circuit generates a gate control signal, and generates an injection signal according to the gate control signal. When a superposition voltage is less than a reference voltage, the control signal generation circuit generates a gate pulse control signal, wherein the gate pulse control signal corresponds to an output voltage of the power converter and the injection signal, the gate control signal generation circuit is further used for generating a gate pulse signal according to the gate pulse control signal, and the gate pulse signal is used for making a primary side of the power converter turned on.

Abstract: A method of switching operational modes of a power converter includes starting up a primary controller applied to the power converter to make the power converter operate in a normal mode; a secondary controller applied to the power converter detecting an output voltage of a secondary side of the power converter and the primary controller detecting an operational frequency of the power converter; if the operational frequency of the power converter is lower than a predetermined frequency and satisfies a first frequency condition, the primary controller controlling the power converter to enter a sleep mode; and when the power converter enters the sleep mode and the output voltage is lower than a trigger voltage, the secondary controller making the primary controller to control the power converter turned on.

Abstract: A control method of a flyback power converter includes a voltage detection pin detecting conduction time of a power switch of a primary side of the flyback power converter, a feedback pin detecting conduction time of a synchronous switch of a secondary side of the flyback power converter, the feedback pin detecting a number of inductor capacitor resonant valleys when the flyback power converter operates in a discontinuous conduction mode, and a high voltage detection pin detecting an input voltage inputted in the flyback power converter; and a controller applied to the flyback power converter making the flyback power converter operate in a quasi-resonant mode when the number of the inductor capacitor resonant valleys is greater than a predetermined number, an operational frequency of the flyback power converter is less than a predetermined frequency, and the input voltage is less than a predetermined voltage.

Abstract: Asymmetric power converter includes an upper bridge switch, a lower bridge switch, a primary winding, a first secondary winding, a second secondary winding, a control circuit. The first secondary winding and the second secondary winding output a first output voltage and a second output voltage of a secondary side of the asymmetric power converter respectively, and voltage polarity of the first secondary winding is different from voltage polarity of the second secondary winding. The control circuit controls the lower bridge switch and the upper bridge switch according to the first output voltage and the second output voltage, respectively.

Abstract: A control method of a flyback power converter includes a voltage detection pin detecting conduction time of a power switch of a primary side of the flyback power converter, a feedback pin detecting conduction time of a synchronous switch of a secondary side of the flyback power converter, the feedback pin detecting a number of inductor capacitor resonant valleys when the flyback power converter operates in a discontinuous conduction mode, and a high voltage detection pin detecting an input voltage inputted in the flyback power converter; and a controller applied to the flyback power converter making the flyback power converter operate in a quasi-resonant mode when the number of the inductor capacitor resonant valleys is greater than a predetermined number, an operational frequency of the flyback power converter is less than a predetermined frequency, and the input voltage is less than a predetermined voltage.

Abstract: An efficiency tracking method of a controller applied to a flyback power converter includes before the controller soft starts, an original frequency variation curve setting voltage generated by the controller outputting an original frequency variation curve setting detection current to an original frequency variation curve setting detection resistor determining a frequency variation curve of the flyback power converter, and utilizing adjustment of resistance of the original frequency variation curve setting detection resistor to achieve efficiency optimization. Therefore, the controller controls an output voltage of the flyback power converter and tracks a maximum power point of the flyback power converter according to the efficiency tracking method to achieve efficiency optimization.

Abstract: A power factor correction (PFC) controller applied to a primary side of a power converter includes a feedback pin, a sensing pin, a current detecting circuit, an output voltage detecting circuit, and a determination circuit. The current detecting circuit is coupled to the feedback pin and the sensing pin for detecting an output current of a secondary side of the power converter according to a feedback voltage of the feedback pin and a sensing voltage of the sensing pin. The output voltage detecting circuit is coupled to the feedback pin for detecting an output voltage of the secondary side of the power converter according to the feedback voltage. The determination circuit is coupled to the current detecting circuit and the output voltage detecting circuit for turning on or turning off a PFC circuit coupled to the power converter according to the output current and the output voltage.

Abstract: A primary controller applied to a primary side of a power converter includes a ripple cancellation circuit, a compensation voltage generation circuit, and a gate control signal generation circuit. The ripple cancellation circuit generates an adjustment according to a current flowing through a feedback pin of the primary controller during turning-on of a power switch of the primary side of the power converter. The compensation voltage generation circuit generates a compensation voltage of a compensation pin of the primary controller according to the adjustment, a reference voltage, and a feedback voltage of the feedback pin. The gate control signal generation circuit generates a gate control signal to the power switch to reduce an output voltage of a secondary side of the power converter according to the compensation voltage and a detection voltage.

Abstract: A voltage mode controller applied to short-circuited protection of a power converter includes gate control signal generation circuit and control circuit. The control circuit generates control signal to make the gate control signal generation circuit generate predetermined signal to power switch of the primary side of the power converter before the power converter starts up and when supply voltage is greater than first reference voltage, enables short-circuited protection after predetermined enabling period of the predetermined signal if detection voltage is less than second reference voltage during the predetermined enabling period. The short-circuited protection makes the power converter not start up, and after the power converter starts up, the short-circuited protection is enabled to turn off the power converter if the detection voltage is less than the second reference voltage for de-bounce time and compensation voltage is greater than third reference voltage.

Abstract: A secondary controller applied to a secondary side of a power converter includes a control signal generation circuit. The control signal generation circuit is coupled to an output terminal of the secondary side of the power converter for detecting an output voltage of the secondary side and enabling a pulse signal to a signal source of the secondary side of the power converter, wherein the signal source enables a turning-on signal according to the pulse signal. The turning-on signal is coupled to a primary-side auxiliary winding of the power converter through a secondary-side auxiliary winding of the power converter to make the primary-side auxiliary winding generate a voltage, and a primary controller of a primary side of the power converter makes the primary side of the power converter be turned on according to the voltage.

Abstract: A transmitting/receiving command method applied between a master controller and a slave controller of a power converter includes enabling the master controller and the slave controller; a controller of the master controller and the slave controller detecting a node voltage of a pin of the controller; the controller transmitting a first command of a plurality of first commands to another controller of the master controller and the slave controller through the pin when the node voltage is less than a predetermined voltage, wherein the predetermined voltage corresponds to over temperature protection of the power converter; and the controller detecting the node voltage again after the controller receives a first return signal transmitted by the another controller.

Abstract: A secondary controller applied to a secondary side of a power converter includes a control signal generation circuit, a voltage detection signal generation circuit, and a gate control signal generation circuit. The control signal generation circuit generates a short-circuited control signal to a short winding switch after a gate control signal to make the short winding switch be turned on. When an output voltage of the power converter is less than a predetermined voltage, the voltage detection signal generation circuit generates a first detection signal to the control signal generation circuit. The control signal generation circuit further generates a gate pulse control signal according to the first detection signal. The gate control signal generation circuit generates a gate pulse signal according to the gate pulse control signal, wherein the gate pulse signal is used for making a primary side of the power converter be turned on.

Abstract: A controller for extending a protection period of a power converter includes a delay circuit. The delay circuit is coupled to a supply voltage pin of the controller. When the power converter enters a protection mode, the delay circuit is enabled, receives a supply voltage through the supply voltage pin, and extends a protection period corresponding to the protection mode according to the supply voltage.

Abstract: A ripple suppressor includes a constant current generation circuit and a voltage regulation circuit. The constant current generation circuit is coupled to a light-emitting diode chain, wherein the constant current generation circuit is used for generating a detection voltage, and generating a constant current to the light-emitting diode chain. The voltage regulation circuit is coupled to the light-emitting diode chain and the voltage regulation circuit, wherein the voltage regulation circuit makes the constant current generation circuit generate the constant current according to the detection voltage and a compensation value, or makes the constant current generation circuit generate the constant current according to the detection voltage, wherein the compensation value is changed with an average voltage generated by the voltage regulation circuit, and the average voltage corresponds to a voltage of an end of the light-emitting diode chain.

Abstract: A multiple output rectifier includes a comparator-based active rectification circuit and a controller, wherein the controller is coupled to the comparator-based active rectification circuit. The comparator-based active rectification circuit is used for generating and outputting each output voltage of a plurality of output voltages according to an input voltage, the each output voltage, and a control signal corresponding to the each output voltage. The controller is used for generating the control signal according to the each output voltage and a reference voltage corresponding to the each output voltage.