Patent ID: 7116565
Filing Date: 2006-10-03
Classification: H02H,H02M

Abstract:
1. An over-power protection circuit for a self-excited power converter, comprising: a soft-start unit, generating a compensating signal in response to a feedback signal of said self-excited power converter, a PWM unit of said self-excited power converter generating a switching signal in response to said compensating signal, wherein said switching signal controls the output power of said self-excited power converter; an adjusting unit, coupled to said soft-start unit in response to an over-power signal and a second threshold signal of said self-excited power converter, wherein said adjusting unit drives said soft-start unit and said PWM unit to modulate said switching signal for reducing the output power of said self-excited power converter once said over-power signal is higher than said second threshold signal; and a timing unit, receiving said over-power signal and a first threshold signal of said self-excited power converter, wherein said timing unit starts to count once said over-power signal is higher than said first threshold signal while said timing unit generates a latch signal to make said self-excited power converter stop supplying power source after the timing unit counting for a period of time.