Other Parts Discussed in Thread: LMG342X-BB-EVM
I am using LMG3425R030 in a full bridge configuration. I have a bypass cap closed to the half bridge which is 136 nF and I have another larger bypass cap relatively far from the half bridge. When I increase the larger bypass cap to be higher than 1 uF, the 12 V aux power current will increase by 0.1 A. And after I turn on the main power, the aux power supply current will drop back to normal value. With higher switching frequency, the aux power supply current will increase more. However, if there is only the 136 nF close bypass cap, the aux power supply current will always be the normal value. I am wondering what could be the reason for this. Thank you!