Patent ID: 7199649
Filing Date: 2007-04-03
Classification: H02M,Y02B

Abstract:
1. A switching power supply unit, for rectifying an AC voltage from an AC power source, switching a rectified voltage supplied to a pulse transformer using a control circuit, and supplying a specified load voltage to a load connected to a secondary winding of the pulse transformer, wherein at the time of normal operation, the rectified voltage is supplied via a first resistor to a power supply terminal of the control circuit, together with supply of a voltage generated at a drive winding of the pulse transformer to the power supply terminal via a diode, and at the time of standby mode operation, a standby signal, indicating that the switching power supply unit has been put into standby mode, is received from outside, and a voltage that is lower than a voltage threshold at which operation of the control circuit is possible is supplied to the power supply terminal.