Forum Post: LM5046 COMP problem

Dear Sir,

I have designed an isolated DCDC converter with LM5046. I have connect an opto-coupler between the REF and the COMP pins same like in the Evaluation Boards schematic. The circuit working with maximal duty cycle, no activ and pasiv operation states. When the secunder side voltage reach the desired value, the opto-coupler start to conduct, but the IC doesn't reduce the PWM duty cycle. When the secunder side voltage rising a little bit more the opto-coupler fully opened, and the HO2 and LO1 signals are getting to confused.

Regards

Akos Bencsura