| 摘要 |
PURPOSE: A circuit for protecting a power supply apparatus and a method thereof are provided to protect a power supply apparatus from generating heat when an over-current is occurred on the power supply apparatus. CONSTITUTION: A switching part(34) selectively outputs an input power in response to a pulse width modulating signal. A power supplying part(36) converts and rectifies the input power transferred from the switching part and generates an output voltage for driving an output load. An abnormal voltage detecting part(20) generates an abnormal voltage detecting signal which is activated when the output voltage is larger than the first reference voltage or smaller than the second reference voltage. An operation control part(30) is activated in response to the activated abnormal voltage detecting signal and generates the first operation stop signal for maintaining the activated state. An over-current detecting part(38) detects whether an over-current flows through the output load and generates the second operation stop signal which is activated when the over-current is detected. A pulse width modulating signal generating part(32) generates the pulse width modulating signal to turn off the switching part in response to the activated first or second operation stop signal.
|
