Abstract: A composite power supply includes a plurality of power cluster lines, at least one USB port and at least one DC port formed on a surface of a casing, and the power cluster lines, the USB port and the DC port are electrically connected to a circuit board and the circuit board includes a plug-and-play circuit electrically connected to the USB port and provided for an electronic device to access electric power through the USB port, so as to waive the inconvenience of booting a computer before using the electric power, and the circuit board includes a DC-DC conversion circuit electrically connected to the DC port, and a knob or a multi-stage switch in the DC-DC conversion circuit is provided for adjusting the output voltage of the power ports to improve the convenience of the application significantly.

Abstract: The present invention discloses a variable frequency PWM synchronous rectifier power supply comprising: a transformer, a PWM control circuit and a synchronous rectification switch circuit. The transformer has a primary side and a secondary side, and an isolation circuit is provided for separating the primary side and the secondary side, and the primary side uses a transmit/receive switch circuit to drive the transformer, and the secondary side uses a filter circuit to output different voltages to an external load. The PWM control circuit is situated on the secondary side and coupled to the isolation circuit and filter circuit, for generating a control signal to the isolation circuit to drive the transmit/receive switch circuit. The synchronous rectification switch circuit is situated on the secondary side and coupled to the PWM control circuit for receiving a timing delay control signal provided by the PWM control circuit.

Abstract: The present invention provides a power supply apparatus for an LED lamp, which mainly uses an isolation transformer to convert a high voltage AC input signal into a low voltage AC signal and thus generate a driving voltage for driving an LED lamp, comprising: a waveform and frequency modulation module disposed on the primary side of the isolation transformer for modulating an input waveform and a frequency f; and a secondary rectifier filter module disposed on the secondary side of the isolation transformer for converting the low voltage AC signal after passing through the isolation transformer into the driving voltage. In this way, the power supply apparatus for an LED lamp utilizes the principle of persistence of vision of human eyes to modulate the waveforms and frequencies of voltages for driving LEDs and can still maintain the normal operation.

Abstract: The present invention provides a power supply apparatus for an LED lamp, which mainly uses an isolation transformer to convert a high voltage AC input signal into a low voltage AC signal and thus generate a driving voltage for driving an LED lamp, comprising: a waveform and frequency modulation module disposed on the primary side of the isolation transformer for modulating an input waveform and a frequency f; and a secondary rectifier filter module disposed on the secondary side of the isolation transformer for converting the low voltage AC signal after passing through the isolation transformer into the driving voltage. In this way, the power supply apparatus for an LED lamp utilizes the principle of persistence of vision of human eyes to modulate the waveforms and frequencies of voltages for driving LEDs and can still maintain the normal operation.

Abstract: A composite power supply includes a plurality of power cluster lines, at least one USB port and at least one DC port formed on a surface of a casing, and the power cluster lines, the USB port and the DC port are electrically connected to a circuit board and the circuit board includes a plug-and-play circuit electrically connected to the USB port and provided for an electronic device to access electric power through the USB port, so as to waive the inconvenience of booting a computer before using the electric power, and the circuit board includes a DC-DC conversion circuit electrically connected to the DC port, and a knob or a multi-stage switch in the DC-DC conversion circuit is provided for adjusting the output voltage of the power ports to improve the convenience of the application significantly.

Abstract: A power device with isolated varying-frequency PWM control contains a transformer having a primary side and a secondary side; a varying-frequency PWM chip located at the secondary side, the varying-frequency PWM chip containing a frequency adjustment circuit and PWM control circuit, the PWM control circuit having at least an output terminal; a sampling circuit connected to the varying-frequency PWM chip; and a separation circuit having at least a terminal connected to the varying-frequency PWM chip; wherein the at least one terminal of the PWM control circuit drives a switch so that various types of transformer is applicable; the frequency adjustment circuit of the varying-frequency PWM chip dynamically adjusts a periodic signal's frequency according to load condition so that a pulse signal from the PWM control circuit is adjusted as well to reduce switching loss and to enhance energy conservation.

Abstract: The present invention discloses a secondary side-driven half-bridge power supply, which has a half-bridge transformer. A MOSFET unit is connected to the primary side of the half-bridge transformer, and an output rectifier/filter circuit connected to the secondary side of the half-bridge transformer. In the present invention, a PWM controller generates a control signal and sends the signal to a separating element. The control signal is used to drive the MOSFET unit, and the MOSFET unit then drives the half-bridge transformer. The output rectifier/filter circuit processes the signal output by the half-bridge transformer to provide voltages for external loads. The present invention can increase the power efficiency, raise the working frequency, and reduce the cost.

Abstract: The present invention discloses a secondary side-driven half-bridge power supply, which has a half-bridge transformer. A MOSFET unit is connected to the primary side of the half-bridge transformer, and an output rectifier/filter circuit connected to the secondary side of the half-bridge transformer. In the present invention, a PWM controller generates a control signal and sends the signal to a separating element. The control signal is used to drive the MOSFET unit, and the MOSFET unit then drives the half-bridge transformer. The output rectifier/filter circuit processes the signal output by the half-bridge transformer to provide voltages for external loads. The present invention can increase the power efficiency, raise the working frequency, and reduce the cost.

Abstract: A parallel connection device for a personal computer is provided. The personal computer includes a motherboard, a first power supplier, and a second power supplier. The parallel connection device includes a first power plug, a second power socket, and a third power socket. The first power plug is connected to a first power socket of the motherboard. Through a second power plug, the first power supplier is connected to the second power socket. Through a third power plug, the second power supplier is connected to the third power socket. Therefore, the load of the first and the second power suppliers can be reduced.

Abstract: A power transmission line for power supply clusters is electrically connected to a personal computer and a power supply cluster to allow the power supply cluster to receive ON/OFF signals and has a signal delay circuit to generate a time difference for the ON/OFF signals so that the power supply cluster delivers power output in an asynchronous fashion to drive the personal computer.