Patent ID: 8648618

Claim:
A method for judging status of power supplies each of which is electrically connected to a motherboard and includes a voltage stabilization and energy storage element located in a power factor correction unit to provide a stabilized voltage upon being activated and a pulse width control unit to drive the power supply to perform power conversion, the method comprising the steps of: establishing comparison voltages: establishing a first comparison voltage, a second comparison voltage smaller than the first comparison voltage and a third comparison voltage smaller than the second comparison voltage; getting the stabilized voltage: getting the stabilized voltage of the voltage stabilization and energy storage element during operation of the power supply; judging external power supply: comparing the stabilized voltage with the first comparison voltage, and judging the external power supply in an abnormal state when the stabilized voltage is smaller than the first comparison voltage and generating an external power supply abnormal signal sent to the motherboard; judging power supply performance: comparing the stabilized voltage with the second comparison voltage, and judging the power supply performance in an abnormal state when the stabilized voltage is smaller than the second comparison voltage and generating a power supply abnormal signal sent to the motherboard; and judging power failure: comparing the stabilized voltage with the third comparison voltage, and judging the power in a failure state when the stabilized voltage is smaller than the third comparison voltage and generating a power failure alert signal sent to the pulse width control unit.