STM32H563VIT3Q Controller Communication Failure During ISO 16750-2:2023 Superimposed Alternating Voltage Test
Hi Team,
We are performing the ISO 16750-2:2023 Superimposed Alternating Voltage test on our DUT. The 12 V main supply is provided to the TPSM64406RCHR buck converter, which generates a nominal 3.3 V supply for the STM32H563VIT3Q controller.
During the test, a 6 V peak-to-peak AC ripple is superimposed on the 12 V input, causing the input voltage to vary between approximately 9 V and 15 V. Under this condition, communication with the STM32 controller fails.
We attempted to reflash the firmware multiple times, but the issue persisted. However, when we performed a Full Chip Erase using STM32CubeProgrammer and then reflashed the firmware, the controller started working properly.
Could you help us identify the possible root cause of this issue and explain why repeated firmware flashing did not resolve it, whereas a full chip erase followed by reflashing restored normal operation? We would also appreciate recommendations for further debugging to determine whether the issue is related to power supply instability, MCU reset or boot behavior, Flash memory contents, or firmware execution during the superimposed alternating voltage test.
Thanks,
Ramesh