Part Number: UCC2803
Hello,
I am using UCC2803 for a dual-output active-clamp flyback converter switching at 1MHz. The input range is 7 V to 28 V and the output is 24 V. I have questions regarding the startup performance.
Previously, the startup performance looked like this:
TI engineer suggested to check the loop stability as the waveforms within the red circle indicate a loop phase margin of less than 20 degree. I couldn't check it by applying a load transient (not fast enough to do that), so I lowered the bandwidth and repeated the test. The new waveforms look as following:
As you can see, over-current protection was not triggered during start-up. But I notice there is a glitch at the Vo. It appears every time. Could you please explain this phenomenon? Thanks.