Tool/software:
Hi every one,
I made an battery charger using sync buck converter with a 48V 30A output. The LM74700 is used as a O-ring at the output side. When testing the board, I found the Vcap of LM74700 will drop from 12V to 6V while the output Current increase to about 15A.
I found that when I add 470pF snubber cap on Q5, the situation get better for the voltage drop occur at about 25A. I also tried to add some ceramic cap on input side and out putside of the chip, but I'm out sure whether it works or not. Is this matter could be explained? why the mosfets behavior while influence the Vcap charge pump?
