Patent ID: 8035999

Claim:
An isolating self-oscillation flyback converter, including a coupling transformer T 1 , a FET TR 1 , a transistor TR 2 , a photoelectric coupling isolator OC 1 and a load feedback circuit Adj, wherein, the common polarity terminal of a feedback winding Nfb of the coupling transformer is connected to the gate of the FET TR 1 via a capacitance C 1 and a resistance R 2 , and connected to the base of the transistor TR 2 via a capacitance C 2 , the base of the transistor TR 2 is also connected to the emitter of the photoelectric coupling isolator OC 1 , and, the photoelectric coupling isolator OC 1 is connected to the load via the feedback circuit, characterized in that, a loop circuit is directly arranged between the feedback winding Nfb and the photoelectric coupling isolator OC 1 , for supplying required power to the photo coupler.