I use a flyback with 4 outputs to supply 6 IGBT pre-driver in a PMSM ECU. Normally my power board is OK. But I met a abnormal phenomenon in one board.
The flyback is with 12V input and 4 lanes of 15V output. When power on with 12V input, the 15V output are OK. But when I want to switch on the IGBT, there is a voltage drop for 15V output as following, the minimum voltage drop to 11V and trig the UVLO of pre-driver. Could you explain why this happen? There is no this phenomenon on another power board.
