Slow increasing voltage MCU (STM32H743) reset

[krishna K H]

Hi team,

We are increasing the Input voltage 0.5 Volts/ Minute to Input of PMIC. PMI switches on after the Input voltage reaches 3.7 volts.

After PMIC switches on it gives 3.3Volt Output but Controller is not getting reset.

If we Power up instantly controller is working fine.

Please support us for resolving this issue.

Thanks,

Krishna

[Tesla DeLorean]

Is BOOT0 Pulled Low?

Have a POR with a higher threshold.

[krishna K H]

yes, Boot0 pin pulled to low.

How to set POR threshold voltage?

Thanks

Krishna

[Piranha]

> Controller is not getting reset

While at low voltages, the MCU is kept in a reset state. Increasing voltage can only release the reset. And, changing the voltage increase slope, changes times at which different external electronics start. Therefore it can easily brake flawed software.

[krishna K H]

Thanks for your response.

can you guide me how to solve this issue.

Regards

Krishna

[Tesla DeLorean]

You should seek guidance from your supervisor.

Are you sure it is not starting? Probably is starting but running into difficulties because other things aren't working.

Instrument Error_Handler() and HardFault_Handler() and any other while(1) loops so you can see if it dies in those.

Use a Power-On-Reset circuit which holds the device in reset until you're actually ready/capable of running. Perhaps an MCP120 3V device. Add one externally as an experiment.