Delta Electronics (shanghai) Co., Ltd

Delta Electronics, Inc.

Haibin Song

Daofei Xu

Jinfa Zhang

Jian Zhou

Qi Fu

Zengyi Lu

Hairui Xu

Shiwei Liu

Milan M Jovanovic

Laszlo Huber

Chien-Chung Chang

Alpha Zhang

Fengkai Jiang

Leyang Yang

Yuanqiang Gu

Jianwei Song

Yunfei Liu

Magnetic core

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.

Power converter and method of control thereof

Present disclosure provides a winding assembly and a magnetic element. The winding assembly includes a circuit board with a central hole and a first winding wound around the central hole in the circuit board; the first winding includes N turns of coil on at least two wiring layers; a second end of at least one turn of coil on a first wiring layers is connected to a first end of next turn of coil at corresponding position on a second wiring layer of the circuit board. The magnetic element includes a magnetic core and a winding assembly sleeved on a magnetic leg.

Winding assembly and magnetic element

The application discloses a converter adaptable to a wide range output voltage and a control method thereof. The converter includes a PWM half-bridge circuit. The control method includes: causing the PWM half-bridge circuit to enter into a DCM by regulating a switching frequency; in each switching period, extending conduction time or turning on a corresponding synchronous rectifier once again for a predetermined time before the first power switch and the second power switch are turned on, to realize zero voltage switching (ZVS) of the first power switch and the second power switch. The application realizes ZVS of the primary power switches, thereby reducing loss.

Converter adaptable to wide range output voltage and control method thereof

A hybrid flyback circuit is provided and includes an upper switch, a lower switch, a transformer, a resonant circuit, a current sampling circuit and a control unit. The control unit includes an output voltage feedback unit, a peak current comparison unit controlling the upper switch to turn off when a sampling voltage corresponding to the current sampling signal is equal to the first voltage feedback signal, a first dead time delay unit controlling the lower switch to turn on after a first dead time starting from the turn-off time of the upper switch, a negative peak current feedback unit for generating a second voltage feedback signal, a conduction control unit controlling the lower switch to turn off, and a second dead time delay unit controlling the upper switch to turn on after a second dead time starting from the turn-off time of the lower switch.

Hybrid flyback circuit and control method

The invention discloses a converter adaptable to a wide range output voltage and a control method thereof. The converter comprises a PWM half-bridge circuit. The control method comprises the steps of: controlling the PWM half-bridge circuit to enter into a discontinuous conduction mode by regulating a switching frequency; when the PWM half-bridge circuit is operated in the discontinuous conduction mode, oscillation occurs among the output inductor, a magnetizing inductor of the transformer and a parasitic capacitor of the PWM half-bridge circuit, and when a center point voltage of the primary switching bridge arm reaches a valley or a peak, turning on the corresponding power switch. The invention reduces switching loss by controlling the corresponding power switch in the PWM half-bridge circuit to turn on when a voltage across the power switch is oscillated to valley.

The present application provides a detecting method of an operating state of a power supply and a detecting apparatus, where the power supply includes a primary circuit, a transformer and a secondary circuit. The secondary circuit includes a secondary current detecting unit, a temperature detecting unit and a secondary controlling unit. Firstly the secondary current detecting unit detects a current value of the secondary circuit, then the secondary controlling unit compares the current value of the secondary circuit with a preset current threshold. When the current value of the secondary circuit is less than or equal to the preset current threshold, the temperature detecting unit detects a temperature value of the power supply and the secondary controlling unit determines the operating state of the power supply according to the acquired temperature value of the power supply.

Detecting method for an operating state of a power supply and a detecting apparatus

A power adapter includes a first output port, a second output port, a motherboard, a first flyback power module, a second flyback power module, a bus capacitor and an EMI module. The first flyback power module has a first circuit board and is electrically connected to the first output port. The second flyback power module has a second circuit board and is electrically connected to the second output port. The EMI module has a third circuit board and is arranged on the motherboard. The first circuit board and the second circuit board are arranged in parallel with each other, and are arranged substantially perpendicular to the motherboard on a first side of the motherboard.

Power adapter

The present disclosure relates to an adapter. The adapter includes an input port, a first output port and a second output port, and the adapter further includes: a rectifier circuit having an input terminal being connected to the input port of the adapter; a bus capacitor connected to an output terminal of the rectifier circuit in parallel; a first flyback converter having an input terminal connected to the bus capacitor and an output terminal coupled to the first output port; and a second flyback converter having an input terminal connected to the bus capacitor and an output terminal coupled to the second output port.

Adapter and control method thereof

Disclosed are a voltage switching circuit and a power adapter having the same. The voltage switching circuit comprises a first switching circuit having a first terminal receiving a first voltage from a first converter, and a second switching circuit having a first terminal receiving a second voltage from a second converter. Second terminals of the first and second switching circuits are electrically connected to form a switching terminal for outputting an output voltage. When the output voltage is required to be switched from the first voltage to the second voltage, the first switching circuit is controlled to be turned off and then the second switching circuit is controlled to be turned on, and when a voltage at the first terminal of the second switching circuit is higher than a preset voltage, the second converter is shut down or kept off.

Voltage switching circuit and power adapter having regulated range of output voltage

A power adapter, includes: a transformer, including a primary winding and a secondary winding; a primary circuit, including a primary main switch, electrically coupled to the primary winding; a secondary circuit, including a first switch unit and a second switch unit; a first end of the first switch unit and a first end of the second switch unit are coupled to the secondary winding of the transformer, and a second end of the first switch unit and a second end of the second switch unit connected to a first output port and a second output port, respectively; a control circuit, configured to detect output voltages of the first output port and the second output port, and controlling the primary main switch, the first switch unit and the second switch unit to adjust the output voltages of the first output port and the second output port.

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.

Magnetic device and method of manufacturing the same

A totem-pole PFC circuit is provided. The totem-pole PFC circuit includes an inductor, a first bridge arm and a second bridge arm. The first bridge arm includes a first switch and a second switch connected in series. A first middle node connected between the first and second switches is coupled to a first terminal of an AC power source through the inductor. The second bridge arm connected to the first bridge arm in parallel includes a third switch and a fourth switch connected in series. A second middle node connected between the third and fourth switches is coupled to a second terminal of the AC power source. When a polarity of the AC power source is changed, a change time of a voltage on the second middle node is longer than a preset time not less than 20 &#x3bc;s.

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Shanghai, China

Haibin Song