Abstract: A magnetic device comprises two base portions and magnetic pillars, wherein each of the two base portions has a first surface and the two first surfaces are faced to each other, and the magnetic pillars are disposed between the two first surfaces along a first direction, wherein, in the first direction, two of the magnetic pillars located at the outermost side of the base portion are a first corner pillar and a second corner pillar respectively, n of the magnetic pillars having the same cross-sectional area and located at the center position of the base portion are n center pillars, and cross-sectional area of the magnetic pillars are gradually increased from the first corner pillar to the center pillar closest to the first corner pillar, and from the second corner pillar to the center pillar closest to the second corner pillar.

Abstract: A flyback converter includes: a transformer, including a primary winding and a secondary winding; a primary side switch electrically coupled to the primary winding; a feedback circuit, configured to detect an output voltage of a load and output a feedback voltage signal; a current detecting circuit, configured to sample current flowing through the primary side switch and output a current signal; and a control circuit, coupled to the feedback circuit and the current detecting circuit and configured to respectively receive the feedback voltage signal and the current signal, and output a switch control signal to the primary side switch; and wherein the control circuit configured to control a switching frequency of the primary side switch to increase with increase of an output power, and an increasing speed of the switching frequency to decrease with the increase of the output power.

Abstract: The present invention discloses a method and an apparatus for controlling a flyback converter, the flyback converter including a main switch, a transformer and an auxiliary switch. The method includes: obtaining a first voltage signal and a second voltage signal, the first voltage signal representing an input voltage of the flyback converter, and the second voltage signal representing an output voltage of the flyback converter; controlling turn-on of the auxiliary switch, wherein the turn-on time period of the auxiliary switch is determined according to the first voltage signal and the second voltage signal; and turning on the main switch at ZVS condition, wherein the main switch is turned on at the time delayed for a duration of a dead time after turning off of the auxiliary switch.

Abstract: A flyback converter includes: a transformer, including a primary winding and a secondary winding; a primary side switch electrically coupled to the primary winding; a feedback circuit, configured to detect an output voltage of a load and output a feedback voltage signal; a current detecting circuit, configured to sample current flowing through the primary side switch and output a current signal; and a control circuit, coupled to the feedback circuit and the current detecting circuit and configured to respectively receive the feedback voltage signal and the current signal, and output a switch control signal to the primary side switch; and wherein the control circuit configured to control a switching frequency of the primary side switch to increase with increase of an output power, and an increasing speed of the switching frequency to decrease with the increase of the output power.

Abstract: A control device applied to a flyback converter including an auxiliary switch includes: an output voltage integrator, configured to integrate an output voltage of the flyback converter to obtain an amplitude of a negative magnetizing current of the flyback converter; and a comparator controller, configured to compare the obtained amplitude of the negative magnetizing current with a reference value, and turn off the auxiliary switch according to a comparison result. According to the present disclosure, it is able to achieve zero voltage switching of a primary-side switch of the flyback converter with variable outputs.

Abstract: A control device, which is applied to a flyback converter including an auxiliary switch, includes: an on-time setter, configured to set an on-time threshold according to a reference value and an output voltage of the flyback converter; and an on-time controller, configured to output a control signal to turn on the auxiliary switch, and turn off the auxiliary switch when on-time of the auxiliary switch reaches the on-time threshold. According to the present disclosure, it is able to achieve zero voltage switching of a primary-side switch of the flyback converter with variable outputs.

Abstract: A control device applied to a flyback converter including an auxiliary switch includes: a current detector configured to detect an amplitude of a current of the flyback converter to obtain an amplitude of a negative magnetizing current of the flyback converter; and a comparator controller configured to compare the amplitude of the negative magnetizing current obtained by the current detector with a reference value, and turn off the auxiliary switch according to a comparison result. According to the present disclosure, it is able to achieve zero-voltage switching of a primary-side switch of the flyback converter with variable outputs.

Abstract: The present disclosure provides a connector protection method in which the connector is used to connect a first device and a second device, and the method includes, a first detection unit of the first device detects a first parameter of the first device; a first controller of the first device obtains a second parameter from the second device through the communication line in the connector; and the first controller determines whether the connector is faulty based on the first parameter and the second parameter.

Abstract: The present invention discloses a power adapter and an electronic device comprising the same. The power adapter comprises a housing, which has a plurality of end faces. The power adapter further comprises a power inlet socket, which is provided on any of the plurality of end faces. The end face on which the power inlet socket is provided, at least another one of the plurality of end faces, and the power inlet socket are formed as one body integrally.

Abstract: A flyback power converter includes a hybrid clamp circuit and a corresponding power management unit that substantially optimizes the performance of the flyback power converter in its entire line and load ranges. The clamp circuit, which is connected in parallel to a primary winding of the flyback transformer, includes a parallel combination of a capacitor and resistor that is connected in series with a parallel combination of a switch and a diode. By sensing the operating conditions, the power management circuit configures the clamp circuit either as a passive clamp or as an active clamp. In the passive-clamp configuration, the switch is kept turned off. In the active-clamp configuration, the switch operates with pulse-width modulation (PWM) which enables ZVS turn-on of the main switch.

Abstract: A control device applied to a flyback converter including an auxiliary switch includes: an output voltage integrator, configured to integrate an output voltage of the flyback converter to obtain an amplitude of a negative magnetizing current of the flyback converter; and a comparator controller, configured to compare the obtained amplitude of the negative magnetizing current with a reference value, and turn off the auxiliary switch according to a comparison result. According to the present disclosure, it is able to achieve zero voltage switching of a primary-side switch of the flyback converter with variable outputs.

Abstract: A control device applied to a flyback converter including an auxiliary switch includes: a current detector configured to detect an amplitude of a current of the flyback converter to obtain an amplitude of a negative magnetizing current of the flyback converter; and a comparator controller configured to compare the amplitude of the negative magnetizing current obtained by the current detector with a reference value, and turn off the auxiliary switch according to a comparison result. According to the present disclosure, it is able to achieve zero-voltage switching of a primary-side switch of the flyback converter with variable outputs.

Abstract: A control device, which is applied to a flyback converter including an auxiliary switch, includes: an on-time setter, configured to set an on-time threshold according to a reference value and an output voltage of the flyback converter; and an on-time controller, configured to output a control signal to turn on the auxiliary switch, and turn off the auxiliary switch when on-time of the auxiliary switch reaches the on-time threshold. According to the present disclosure, it is able to achieve zero voltage switching of a primary-side switch of the flyback converter with variable outputs.

Abstract: A flyback power converter includes a hybrid clamp circuit and a corresponding power management unit that substantially optimizes the performance of the flyback power converter in its entire line and load ranges. The clamp circuit, which is connected in parallel to a primary winding of the flyback transformer, includes a parallel combination of a capacitor and resistor that is connected in series with a parallel combination of a switch and a diode. By sensing the operating conditions, the power management circuit configures the clamp circuit either as a passive clamp or as an active clamp. In the passive-clamp configuration, the switch is kept turned off. In the active-clamp configuration, the switch operates with pulse-width modulation (PWM) which enables ZVS turn-on of the main switch.

Abstract: The present disclosure discloses a PCB winding transformer and a coil board thereof. The PCB winding transformer comprises a coil board and a magnetic core. The coil board includes a primary coil and a secondary coil. The primary coil and the secondary coil are wound around a magnetic core column of the magnetic core. At least two via holes which correspond to the primary coil and the secondary coil respectively are disposed in the coil board. In the primary coil and the secondary coil, the via hole corresponding to the coil with less turns is disposed between an inner side of the coil with more turns and the magnetic core column.

Abstract: The present invention discloses a control method and a control apparatus for a Flyback circuit. The Flyback circuit includes a primary switch, a secondary rectifier unit, a transformer and an output capacitor. The secondary rectifier unit includes a first terminal and a second terminal, which are electrically connected to the transformer and the output capacitor, respectively. In the control method for a Flyback circuit, after the secondary rectifier unit is controlled to be turned on once or twice according to the input voltage and/or output power of the Flyback, the primary switch is turned on to achieve the zero-voltage-switching. According to the invention, the zero-voltage-switching (ZVS) of the primary switch can be achieved under the entire input voltage range and the entire load range without adding additional power devices.

Abstract: The present invention discloses a control method and a control apparatus for a Flyback circuit. The Flyback circuit includes a primary switch, a secondary rectifier unit, a transformer and an output capacitor. The secondary rectifier unit includes a first terminal and a second terminal, which are electrically connected to the transformer and the output capacitor, respectively. In the control method for a Flyback circuit, after the secondary rectifier unit is controlled to be turned on once or twice according to the input voltage and/or output power of the Flyback, the primary switch is turned on to achieve the zero-voltage-switching. According to the invention, the zero-voltage-switching (ZVS) of the primary switch can be achieved under the entire input voltage range and the entire load range without adding additional power devices.

Abstract: A switching power supply includes: a rectifying unit; a Bulk capacitor; a converter; a monitoring circuit; a control circuit, controlling discharging of the Bulk capacitor, being configured to perform controls such that the voltage across the Bulk capacitor maintains the peak value after the Bulk capacitor having been charged to a peak value of AC voltage, and to perform controls such that the Bulk capacitor discharges from a peak value when the instantaneous absolute value of the AC voltage is smaller than or equal to the preset voltage. A method for controlling a voltage of a Bulk capacitor in the switching power supply includes detecting an instantaneous absolute value of the AC voltage; comparing the detected instantaneous absolute value of the AC voltage with a preset voltage; and controlling discharging and charging state of the Bulk capacitor according to comparison results.

Abstract: The disclosure relates to a control device, a control method of a power converter and a switching power supply using the control device. The control device of the power converter includes: a first control unit, which is coupled to the power converter to detect an output voltage of the power converter and is configured to generate a first control signal based on the output voltage; a variable resistor unit, which is connected to an output terminal of the first control unit to receive the first control signal and is configured to generate a resistance value based on the first control signal; and a second control unit, which is connected to the variable resistor unit and is configured to output a second control signal in order to control operations of a switch unit of the power converter.