| 摘要 |
An SMPS feedback power source is provided to decrease power consumption of the power source during a standby mode by arranging a dynamic snubber circuit between a first rectifier block and a main switch IC. An SMPS(Switching Mode Power Supply) feedback power source includes a dynamic snubber circuit(22) which suppresses a surge voltage generated at a main switch IC. The dynamic snubber circuit has a resistance which is varied according to a feedback voltage. The dynamic snubber circuit includes an FET(Field Effect Transistor) and plural resistors. The FET is turned on/off by the feedback voltage. The resistors operate as a load resistor according to the on/off process of the FET. During an operation mode, the resistance of the dynamic snubber circuit is decreased. During a standby mode, the resistance of the dynamic snubber circuit is increased. |
