An active flyback converter is transitioned between a plurality of operational states based on a comparison of a control voltage signal to voltage thresholds and a count of a number of consecutive switching cycles during which a clamp switch is kept off. The plurality of operational states includes a run state, an idle state, a first burst state, and a second burst state. Each set of consecutive switching cycles of the first burst state includes a determined number of switching cycles during which signals are generated to turn the power switch on and off and to maintain an off state of the clamp switch, and a switching cycle in a determined position in the set of switching cycles during which signals are sequentially generated to turn the power switch on, turn the power switch off, turn the clamp switch on and turn the clamp switch off.

System and method for controlling turning on a first transistor and turning off a second transistor. For example, a system for controlling turning on a first transistor and turning off a second transistor includes: a logic signal generator configured to: process information associated with a first voltage related to a second voltage of a first auxiliary winding, the first auxiliary winding being coupled to a primary winding, a secondary winding, and a second auxiliary winding; generate a third voltage based on at least information associated with the first voltage, the third voltage indicating a first voltage difference from a drain terminal to a source terminal of a first transistor related to the primary winding; process information associated with the third voltage and a reference voltage; and change a logic signal from a first logic level to a second logic level.

A frequency regulating circuit for a switching circuit, a frequency regulating method, and the switching circuit are provided. The frequency regulating circuit includes a charging current generating module configured to receive a first signal characterizing an output power and a second signal characterizing an input voltage to generate a charging current and a signal generating module configured to output a third signal according to the charging current. The third signal is used to adjust the maximum operating frequency of the switching circuit so that the maximum operating frequency decreases with the increase of the input voltage. Therefore, the frequency regulating circuit increases the maximum operating frequency of the switching circuit under the condition of low voltage input, which decreases the maximum operating frequency of the switching circuit under the condition of high voltage input to reduce the switching loss of the switching circuit with wide input voltage and improve efficiency.

Disclosed are a high-efficiency integrated power circuit with a reduced number of semiconductor elements and a control method thereof. A high-efficiency integrated power circuit of an integrated converter includes an input port, which is a first port, to which power for driving the integrated converter is input, a non-isolated port, which is a second port, for outputting, to outside the high-efficiency integrated power circuit, an allowable amount of power generated when power input through the input port passes through an inductor, and an isolated port, which is a third port, for conducing remaining power excepting power output through the non-isolated port and for maintaining the conducted remaining power inside the high-efficiency integrated power circuit.

A power converter includes a power switch controlling current flow in the power converter and a variable capacitance coupled in parallel to the power switch. The variable capacitance is configured to add a frequency jitter to the power converter.

A flyback power converter includes a controller, a high-end driving circuit, an active clamp switch, a main switch and a zero current detection circuit. The high-end driving circuit is coupled to the controller. The active clamp switch is coupled to the high-end driving circuit for driving the active clamp switch. The main switch is coupled to the controller. The zero current detection circuit is coupled to the controller. The main switch and the active clamp switch are arranged on the primary side of a transformer. The switching period of a gate of the active clamp switch and the switching period of a gate of the main switch are controlled in reverse phase to achieve zero voltage or zero current conversion.

A system, method, and non-transitory computer-readable medium are disclosed for intelligently controlling a power supply system of an information handling system. At least one embodiment is directed to a method that includes receiving power from an adapter and providing the power from the adapter to a switching power supply. At least one embodiment of the method also includes controlling the plurality of power switching elements to provide system power to an information handling system through the switching power supply; detecting a light loading power condition of the information handling system. In response to detecting the light loading power condition, the switching power supply is deactivated and a bypass control module is activated. In at least one embodiment, activation of the bypass control module directs power from the adapter through the bypass control module to the information handling system as the system power.

A power source apparatus including: a transformer including a primary coil, a secondary coil, and an auxiliary coil, and has a primary side and a secondary side which are insulated from each other; a rectifier circuit including a first output terminal and a second output terminal; a smoothing capacitor; a switching element; a first series circuit having a capacitor and a first rectification element connected in series; and a second series circuit having a second rectification element and the auxiliary coil connected in series. The number of turns of the auxiliary coil is smaller than the number of turns of the primary coil. A product a ratio between the number of turns of the auxiliary coil and the number of turns of the secondary coil and an output voltage on the secondary side of the transformer is equal to or lower than a voltage of the smoothing capacitor.

A method for controlling a power conversion device can prevent over temperature by suppressing a change in impedance of a capacitor included in a rectifier circuit. The power conversion device includes an AC wave generation circuit for generating an AC wave, and a rectifier circuit for rectifying the AC wave generated by the AC wave generation circuit with a configuration including a rectifier capacitor and a diode connected in parallel. The method for controlling the power conversion device regulates the AC wave input to the rectifier capacitor depending on a change in impedance of the rectifier capacitor so as to suppress the change in the impedance of the rectifier capacitor.

A DC-DC power converter employs a full bridge series resonant converter topology with a resonant tank and two transformers, one before and one after the resonant tank, to obtain a high voltage (e.g., approximately 300V, approximately 1500V or greater) output from a relatively low voltage (e.g., approximately 9V-16V) input, for instance an input from one or more battery cells. DC-DC power converter is operable to output high voltage (e.g., around 300V, 1500V or higher) short duration pulses (e.g., tens of nanoseconds or less). A burst mode control technique provides as good regulation characteristics at light loads. Instead of turning OFF the active switches during an OFF period, the switches are operated at a different frequency (e.g., higher frequency) during the OFF period than a frequency at which the switches are turned ON during the ON period. Auxiliary loads can also be supplied.