Abstract: A circuit includes a work-power module, an electronic component, a switching apparatus, and a power control unit. The power control unit includes an input pin connected to the work-power module, an output pin connected to the electronic component, and a control pin connected to the switching apparatus. The switching apparatus is capable of controlling the status of the power control unit. Upon the condition that the power control unit is turned on, the work-power module is capable of supplying power to the electronic component. Upon the condition that the power control unit is turned off, the work-power module is not capable of supplying power to the electronic component.

Abstract: A power saving control system includes a power supply, a voltage conversion unit, an electrical switch, a control chip having a general programmable input output (GPIO) pin and a basic input system (BIOS) chip. The power supply is configured for supplying a voltage. The voltage conversion unit is connected to the power supply to receive the voltage and configured for converting the voltage into a working voltage of an electronic element, and outputting the working voltage. The electrical switch is connected between the voltage conversion unit and an input terminal of the electronic element. The control chip is connected to the electrical switch. The BIOS chip is connected to the control chip to control the electrical switch to be turned on or off via controlling an output value of the GPIO pin of the control chip to control the electrical element to work.

Abstract: A circuit includes a work-power module, an electronic component, a switching apparatus, and a power control unit. The power control unit includes an input pin connected to the work-power module, an output pin connected to the electronic component, and a control pin connected to the switching apparatus. The switching apparatus is capable of controlling the status of the power control unit. Upon the condition that the power control unit is turned on, the work-power module is capable of supplying power to the electronic component. Upon the condition that the power control unit is turned off, the work-power module is not capable of supplying power to the electronic component.

Abstract: A power control circuit of a universal serial bus (USB) includes a USB interface, a north bridge chipset and a current control circuit. The USB interface has a power pin and a plurality of data pins. The north bridge chipset has a state pin and a plurality of signal pins connected to the data pins of the USB interface respectively. The current control circuit is connected between the power pin of the USB interface and the state pin of the north bridge chipset, the north bridge chipset controls the state of the current control circuit and further controls the output power at the power pin of the USB interface. The power control circuit can offer different output powers in accordance with different external devices.

Abstract: A power control circuit of a universal serial bus (USB) includes a USB interface, a north bridge chipset and a current control circuit. The USB interface has a power pin and a plurality of data pins. The north bridge chipset has a state pin and a plurality of signal pins connected to the data pins of the USB interface respectively. The current control circuit is connected between the power pin of the USB interface and the state pin of the north bridge chipset, the north bridge chipset controls the state of the current control circuit and further controls the output power at the power pin of the USB interface. The power control circuit can offer different output powers in accordance with different external devices.