Active filter for computer, filter module, power module and computer

摘要

A signal PWR is driven into a low level in response to a power-off command from the computer, then the low level PWR signal is entered to an input terminal 36 of a switching circuit 130 and regulators 152 to 156 respectively. Consequently, the regulators come to rest and thereby the power supply to the computer is shut off. Receiving the low level PWR signal, a photo-coupler 134 and a transistor 132 in the switching circuit 130 are turned off respectively, as well as the operation of a power factor correction circuitry is stopped. Consequently, an AC power factor correction circuitry comes to rest when the power supply to the computer is shut off, and thereby the power consumption of the computer can be reduced.