A method for controlling an amount of power delivered to an electrical load may include controlling an average magnitude of a load current towards a target load current that ranges from a maximum-rated current to a minimum-rated current in a normal mode, and controlling the average magnitude of the load current below the minimum-rated current in a burst mode. The burst mode may include at least one burst-mode period that comprises a first time period associated with an active state and a second time period associated with an inactive state. During the burst mode, the method may include regulating a peak magnitude of the load current towards the minimum-rated current during the active state, and stopping the generation of at least one drive signal during the inactive state to control the average magnitude of the load current to be less than the minimum-rated current.

A power supply control circuit for controlling a charging process of a power supply capacitor to produce a power supply voltage to power a power control chip is disclosed. The power supply control circuit has a charging switch controlled by a charging control signal, and the power supply capacitor is coupled to an input voltage when the charging switch is on. The power supply control circuit further has a charging control circuit, configured to provide the charging control signal to control the charging switch based on the input voltage, the power supply voltage and a voltage threshold. Thus a high turns ratio of an auxiliary winding to a secondary winding is not necessary, high voltage devices are not needed and the power dissipation caused by the high voltage is also reduced.

Provided are a power supply conversion circuit and a power supply conversion method. The power supply conversion circuit includes a first direct-current conversion circuit connected to an electric load, a secondary transformer coil connected to the first direct-current conversion circuit, and a primary transformer coil coupled to the secondary transformer coil. The primary transformer coil is configured to generate, based on an initial voltage inputted to the primary transformer coil, an electromagnetic field and couple the electromagnetic field to the secondary transformer coil. The secondary transformer coil is configured to generate an induced current by virtue of the electromagnetic field, generate a secondary output voltage based on the induced current, and transmit the secondary output voltage to the first direct-current conversion circuit. The first direct-current conversion circuit is configured to adjust, based on a predetermined demand voltage of the electric load, the secondary output voltage to obtain a target voltage.

A power supply conversion circuit and a charging device are provided. The power supply conversion circuit includes: a first voltage conversion circuit that converts a voltage when the voltage exceeds a preset voltage range and outputs the converted voltage; a post-stage voltage conversion circuit that receives the converted voltage and converts the converted voltage into a target voltage for outputting; and a signal feedback circuit that feeds back a signal to the first voltage conversion circuit according to the target voltage, so that the first voltage conversion circuit is synchronized with the post-stage voltage conversion circuit.

Disclosed in the embodiments of the present application is a power conversion circuit, comprising a direct current conversion circuit, a pulse width control circuit, and a transformer. The transformer comprises a primary transformer coil and a secondary transformer coil. The direct current conversion circuit is connected to the primary transformer coil, and is used for adjusting an initial voltage inputted to the direct current conversion circuit to a target voltage. The pulse width control circuit is connected to the primary transformer coil, and is used for generating a pulse square wave on the basis of the target voltage. The primary transformer coil is coupled with the secondary transformer coil. The primary transformer coil is used for generating an electromagnetic filed according to the pulse square wave, and coupling the electromagnetic field to the secondary transformer coil so that the secondary transformer coil generates an output voltage.

A power converter with over temperature protection compensation includes a main conversion unit, a primary-side control unit, a secondary-side control unit, a secondary detection circuit, and an over temperature adjustment circuit. The secondary-side control unit obtains a secondary voltage change value through the secondary detection circuit, and the secondary-side control unit correspondingly provides a current change value to the over temperature adjustment circuit according to the secondary voltage change value. The over temperature adjustment circuit provides a temperature control voltage according to the current change value so that the secondary-side control unit determines whether an over temperature protection is activated according to the temperature control voltage.

The present disclosure relates to a driving control circuit, method and device for a gallium nitride (GaN) transistor, and a medium. An ADriver pin and an electronic switch are added to an existing flyback power supply circuit. The electronic switch includes a first terminal connected to the ADriver pin, a second terminal connected between a driving resistor and a GaN transistor, and a third terminal connected between a current detection resistor and a current sense pin. By improving the driving control circuit and the driving control method for the GaN transistor, the present disclosure can effectively prevent the false turn-on problem due to high-frequency oscillation between the leakage inductance of the transformer and the parasitic capacitance after the GaN transistor is turned off, and drives the GaN transistor more reliably.

A power supply circuit for a switching mode power supply, having: a charging capacitor coupled to an auxiliary winding; a power supply diode coupled to a power supply capacitor, wherein the charging capacitor has a connecting terminal coupled to the power supply diode, and the charging capacitor and the power supply diode are serially coupled between the auxiliary winding of the switching mode power supply and the power supply capacitor; and a power supply switch coupled between the connecting terminal and a primary ground of the switching mode power supply.

A control circuit for a resonant converter, can include: a feedforward circuit configured to generate a feedforward current; a charge feedback circuit configured to receive a resonant current sampling signal representing a resonant current of the resonant converter in a first mode to generate a charge feedback signal, and to receive the resonant current sampling signal and the feedforward current together to generate the charge feedback signal in a second mode; and a driving control circuit configured to generate driving signals according to the charge feedback signal and a first threshold signal, in order to control switching states of power transistors of the resonant converter, where the first threshold signal is generated according to an error compensation signal representing an error information between a feedback signal of an output signal of the resonant converter and a reference signal.

The synchronous rectifier controller includes a voltage regulator to provide a control voltage to the control terminal of the rectifier switch. The synchronous rectifier controller compares the channel voltage of the rectifier switch with a threshold voltage to generate a comparison result signal. When the channel voltage is greater than the threshold voltage, the comparison result signal has a first logic value, and when the channel voltage is less than the threshold voltage, the comparison result signal has a second logic value. An inverted comparison result signal is generated according to the comparison result signal. When the channel voltage is less than the threshold voltage, the inverted comparison result signal enables a pull-up power supply to pull up the control voltage; and when the channel voltage is greater than the threshold voltage, the comparison result signal enables a pull-down power supply to pull down the control voltage.