2019-11-14 07:52 AM
2019-11-14 08:11 AM
Hello, please check this issue with Arrow. Usually linked to SMPS inductors. Noise could disappear when power load increase.
Not linked to STM32MP15 component.
2019-11-14 09:13 AM
I don't have the board, but in general some switching supplies will whistle / squeal at the edge of the hearing range, the pitch / presence can change with loading, or lack of it.
2019-11-14 09:19 AM
Also it is very often MLCC capacitor. There is simple test, take srewdriver and touch (don't short!) ceramit part of capacitors and inductors. When spotting correct one, the sound will change. MLCCs with class 2 dielectrics are quite a lot microphonics.