Patent ID: 9276483
Filing Date: 2016-03-01
CPC Classification: H02M,Y02B

Claim Text:
1. A control circuit of an active-clamp flyback power converter comprising: a low-side transistor coupled to switch a transformer; a high-side transistor connected in series with a capacitor to develop an active-clamp circuit, wherein said active-clamp circuit is coupled in parallel with said transformer; a high-side driving circuit coupled to drive said high-side transistor; and a controller generating a switching signal and an active-clamp signal, wherein said switching signal is coupled to drive said low-side transistor, and said switching signal is generated in response to a feedback signal for regulating an output of said active-clamp flyback power converter, and wherein said active-clamp signal is coupled to said high-side driving circuit for controlling said high-side transistor, said active-clamp signal comprises a pulse having a rising edge and a falling edge, and a time point of said falling edge is determined by a first resistor.