US Patent 7816817 Power supply circuit on motherboard

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.