2023-05-16 12:53 PM
2023-05-16 02:12 PM
There are signal pins (SWD, UART) from ST-LINK MCU to the L152RE which will "power" the L152RE when Vdd is not connected (J5 open). The GPIO protection diodes are then in the forward direction, which also explains the voltage drop of ~0.7V
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KnarfB