We are currently using the ST1PS02BQTR for powering a compact main board with BT connectivity (STM32WB5MMG), an IMU, and other ancillary blocks (LEDs, charge pump for LEDs, passives). The system is powered through two AAA batteries connected in series. A daughter board (connected with cables) is used for color sensing purpose. Please find attached part of the schematic with the sections of interest. The issue we are experiencing is that one sample out of the pre-series batch (100 units) has a power supply with more significant noise than expected and, after tracking down the issue, we have found it to be related to the specific ST1PS02BQTR component. This issue leads to a faulty Bluetooth connectivity. Changing the specific component with another one solves the issue, swapping the specific component with the one of another working board swaps the issue (i.e. the faulty board works properly, the working board becomes faulty). Please find attached the noisy power supply screenshot (1016_vdd_mcu.png) and a correct power supply (1016_vdd_mcu_app_newDCDC.png). Do you have any insight to share? Do you think it is a component specific issue and therefore we need to understand the cause (handling, other) or is it an in-specs behavior? Thanks a lot.
