Abstract: A DC-to-DC converter includes a first DC side, a second DC side, a first capacitor, a first switch circuit, a magnetic element circuit, a second switch circuit, and a second capacitor. The DC-to-DC converter is adapted for converting between a first DC voltage and a second DC voltage. The magnetic element circuit is electrically coupled to the first switch circuit, and includes a plurality of magnetically coupled windings and an inductor. An oscillating current flowing in the first switch circuit is generated by controlling the first switch circuit and the second switch circuit, and an oscillating frequency of the oscillating current is determined by the capacitance of the first capacitor and the inductance of the inductor in the magnetic element circuit, and the first switch circuit and the second switch circuit are switched at a specific region of a wave trough of the oscillating current.

Abstract: A control unit is provided. The control unit is configured to provide a control signal for controlling a power unit. The power unit includes a first positive voltage terminal, a second positive voltage terminal, a first negative voltage terminal, a second negative voltage terminal, and a switching element. The first negative voltage terminal and the second positive voltage terminal are coupled to each other in a short circuit manner. One terminal of the switching element is electrically connected to the first negative voltage terminal. The control unit is configured to: receive a pulse width modulation signal; receive a first power supply signal; receive a second positive voltage terminal signal; output a second power supply signal; and output the control signal for controlling the switching element to be turned on or turned off.

Abstract: A converter includes an input capacitor, a primary-side switching circuit, a magnetic element circuit, a secondary-side switching circuit, and an output capacitor. The magnetic element circuit includes a transformer and an inductor. The input capacitor is configured to receive an input voltage. The primary-side switching circuit is coupled to the input capacitor. The magnetic element circuit is coupled to the primary-side switching circuit. The secondary-side switching circuit is coupled to the magnetic element circuit. The output capacitor is coupled to the secondary-side switching circuit. The input capacitor, the inductor, and the output capacitor oscillate to generate an oscillating current. The primary-side switching circuit is switched between a peak point of the oscillating current and a valley point of the oscillating current.

Abstract: A DC-to-DC converter includes a first DC side, a second DC side, a first capacitor, a first switch circuit, a magnetic element circuit, a second switch circuit, and a second capacitor. The DC-to-DC converter is adapted for converting between a first DC voltage and a second DC voltage. The magnetic element circuit is electrically coupled to the first switch circuit, and includes a plurality of magnetically coupled windings and an inductor. An oscillating current flowing in the first switch circuit is generated by controlling the first switch circuit and the second switch circuit, and an oscillating frequency of the oscillating current is determined by the capacitance of the first capacitor and the inductance of the inductor in the magnetic element circuit, and the first switch circuit and the second switch circuit are switched at a specific region of a wave trough of the oscillating current.

Abstract: A converter includes an input capacitor, a primary-side switch circuit, a magnetic element circuit, a secondary-side switch circuit, and an output capacitor. The magnetic element circuit includes a transformer and an inductor. The input capacitor is configured to receive an input voltage. The primary-side switch circuit is coupled to the input capacitor. The magnetic element circuit is coupled to the primary-side switch circuit. The inductor is a leakage inductor of the transformer or an external inductor coupled between the transformer and the primary-side switch circuit. The secondary-side switch circuit is coupled to the magnetic element circuit. The output capacitor is coupled to the secondary-side switch circuit. The input capacitor and the inductor generate an oscillating current. The primary-side switch circuit is switched at an adjacent region of a wave trough of the oscillating current.

Abstract: A control unit is provided. The control unit is configured to provide a control signal for controlling a power unit. The power unit comprises a first positive voltage terminal, a second positive voltage terminal, a first negative voltage terminal, a second negative voltage terminal, and a switching element. The first negative voltage terminal and the second positive voltage terminal are coupled to each other in a short circuit manner. One terminal of the switching element is electrically connected to the first negative voltage terminal. The control unit is configured to: receive a pulse width modulation signal; receive a first power supply signal; receive a second positive voltage terminal signal; output a second power supply signal; and output the control signal for controlling the switching element to be turned on or turned off.

Abstract: A converter includes an input capacitor, a primary-side switch circuit, a transformer, an inductor, a secondary-side switch circuit, and an output capacitor. The primary-side switch circuit includes a first and a second bridge arm. Each of the first and the second bridge arm includes at least two switches. A soft-start period of an output voltage from the converter includes a voltage rising period of the output voltage. A turn-on time of one of the at least two switches of the first bridge arm is less than ½ of a switching period. A turn-on time of one of the at least two switches of the second bridge arm is zero of the switching period or near zero of the switching period. The inductor and parasitic capacitors of the at least two switches of the second bridge arm oscillate, and energy generated from an oscillation is transmitted to the second-side switch circuit.

Abstract: A converter includes an input capacitor, a primary-side switching circuit, a magnetic element circuit, a secondary-side switching circuit, and an output capacitor. Primary-side switching circuit includes a first positive voltage terminal and a first negative voltage terminal. First positive voltage terminal is coupled to one terminal of an input voltage. First negative voltage terminal and first positive voltage terminal are coupled to the input capacitor. Magnetic element circuit is coupled to primary-side switching circuit. Secondary-side switching circuit is coupled to magnetic element circuit. Secondary-side switching circuit includes a second positive voltage terminal and a second negative voltage terminal. Second positive voltage terminal is coupled to first negative voltage terminal. Second negative voltage terminal is coupled to another terminal of the input voltage, and second negative voltage terminal and second positive voltage terminal output an output voltage together.

Abstract: A converter includes an input capacitor, a primary-side switching circuit, a magnetic element circuit, a secondary-side switching circuit, and an output capacitor. Primary-side switching circuit includes a first positive voltage terminal and a first negative voltage terminal. First positive voltage terminal is coupled to one terminal of an input voltage. First negative voltage terminal and first positive voltage terminal are coupled to the input capacitor. Magnetic element circuit is coupled to primary-side switching circuit. Secondary-side switching circuit is coupled to magnetic element circuit. Secondary-side switching circuit includes a second positive voltage terminal and a second negative voltage terminal. Second positive voltage terminal is coupled to first negative voltage terminal. Second negative voltage terminal is coupled to another terminal of the input voltage, and second negative voltage terminal and second positive voltage terminal output an output voltage together.

Abstract: A converter includes an input capacitor, a primary-side switching circuit, a magnetic element circuit, a secondary-side switching circuit, and an output capacitor. The magnetic element circuit includes a transformer and an inductor. The input capacitor is configured to receive an input voltage. The primary-side switching circuit is coupled to the input capacitor. The magnetic element circuit is coupled to the primary-side switching circuit. The secondary-side switching circuit is coupled to the magnetic element circuit. The output capacitor is coupled to the secondary-side switching circuit. The input capacitor, the inductor, and the output capacitor oscillate to generate an oscillating current. The primary-side switching circuit is switched between a peak point of the oscillating current and a valley point of the oscillating current.

Abstract: A converter includes an input capacitor, a primary-side switch circuit, a transformer, an inductor, a secondary-side switch circuit, and an output capacitor. The primary-side switch circuit includes a first and a second bridge arm. Each of the first and the second bridge arm includes at least two switches. A soft-start period of an output voltage from the converter includes a voltage rising period of the output voltage. A turn-on time of one of the at least two switches of the first bridge arm is less than ½ of a switching period. A turn-on time of one of the at least two switches of the second bridge arm is zero of the switching period or near zero of the switching period. The inductor and parasitic capacitors of the at least two switches of the second bridge arm oscillate, and energy generated from an oscillation is transmitted to the second-side switch circuit.

Abstract: A converter includes an input capacitor, a primary-side switch circuit, a magnetic element circuit, a secondary-side switch circuit, and an output capacitor. The magnetic element circuit includes a transformer and an inductor. The input capacitor is configured to receive an input voltage. The primary-side switch circuit is coupled to the input capacitor. The magnetic element circuit is coupled to the primary-side switch circuit. The inductor is a leakage inductor of the transformer or an external inductor coupled between the transformer and the primary-side switch circuit. The secondary-side switch circuit is coupled to the magnetic element circuit. The output capacitor is coupled to the secondary-side switch circuit. The input capacitor and the inductor generate an oscillating current. The primary-side switch circuit is switched at an adjacent region of a wave trough of the oscillating current.

Abstract: A power adapter with voltage-stabilized compensation includes a pulse frequency modulation circuit to generate a driving pulse which has a variable OFF time interval to control power transformed and output by a transformer. The power adapter also has an ancillary coil to induce a feedback signal on the secondary coil of the transformer. The pulse frequency modulation circuit includes a time interval modulation unit to receive the feedback signal and a feedback compensation unit. The time interval modulation unit sets a level voltage compared with the feedback signal to generate a sample signal to modulate the OFF time interval. The feedback compensation unit provides a compensation signal to the time interval modulation unit to change the size of the feedback signal or sample signal thereby to compensate the voltage output from the secondary side.

Abstract: A power adapter with voltage-stabilized compensation includes a pulse frequency modulation circuit to generate a driving pulse which has a variable OFF time interval to control power transformed and output by a transformer. The power adapter also has an ancillary coil to induce a feedback signal on the secondary coil of the transformer. The pulse frequency modulation circuit includes a time interval modulation unit to receive the feedback signal and a feedback compensation unit. The time interval modulation unit sets a level voltage compared with the feedback signal to generate a sample signal to modulate the OFF time interval. The feedback compensation unit provides a compensation signal to the time interval modulation unit to change the size of the feedback signal or sample signal thereby to compensate the voltage output from the secondary side.