| 摘要 |
PROBLEM TO BE SOLVED: To provide an insulated switching power-supply device with a simple configuration that allows setting a low-power standby mode without using a photocoupler.SOLUTION: An insulated switching power-supply device includes: a control circuit causing AC power on a secondary winding and an auxiliary winding of an insulated transformer by on/off-controlling a switching element connected to an input power supply via a primary winding of the insulated transformer; an output circuit rectifying and outputting the AC power caused on the secondary winding; an internal power-supply circuit generating a drive power-supply voltage to the control circuit from the AC power caused on the auxiliary winding; output-voltage detection means controlling drive of the switching element through the control circuit by feeding back an output monitor voltage calculated from the drive power-supply voltage to the control circuit; and output-voltage control means changing the level of the output monitor voltage calculated from the drive power-supply voltage according to changes of on/off drive conditions of the switching element in the control circuit. |
