Patent ID: 7586346

Claim:
A power good signal generating circuit for a motherboard, comprising: a charge circuit comprising a first resistor and a capacitor, a system power being grounded via a first transistor and the capacitor in sequence; the first transistor, the base of the first transistor receiving a PS_ON signal from the motherboard, the collector of the first transistor connected to a node between the first resistor and the capacitor, the emitter of the first transistor being grounded; a second transistor, the gate of the second transistor connected to the collector of the first transistor, the drain of the second transistor connected to a standby power, the source of the second transistor being grounded; and a third transistor, the base of the third transistor connected to the drain of the second transistor, the collector of the third transistor connected to the system power, for outputting a PWR_GOOD signal, the emitter of the third transistor being grounded.