Hey guys,
We have recently designed a custom board that incorporated the BQ25150 chip. Now that we have received our first prototype of the board, we realized that the PMID capacitor was producing a buzzing sound which seems very unusual. The capacitor being used on the PMID pin is a 10uF capacitor rated at 25V as recommended by the datasheet. The buzzing sound is not persistent, when we provide Vin, it usually starts off without any problem but then it appears randomly at some point, we were not able to completely narrow down the instance at which the buzzing sound starts. I have provided the schematic for the part of the chip, ignore the 22uF chip at the PMID pin, it was later replaced. Also, something to note is that the 4.7uF cap at the IN pin is only rated at 10V. Could anyone provide any insights into this problem? Any help would be appreciated. Feel free to ask for more information.