Skip to main content
Associate
December 26, 2025
Question

Continuous Reboot Issue with STM32G070CBT6

  • December 26, 2025
  • 5 replies
  • 445 views

Hello,

We are currently using the STM32G070CBT6 microcontroller in one of our data logger devices, which operates on a three-phase power supply and is used in a transformer application. In our design, the microcontroller triggers a relay, and the relay controls a contactor.

 

We are facing an issue where the STM32G070CBT6 is continuously rebooting during normal operation, which is affecting the overall functionality and reliability of the product.

 

For your reference, we have attached the reset circuit schematic used in our design. We kindly request you to review the schematic and help us identify the possible causes of the continuous reboot behavior.

 

Please let us know if any additional information, measurements, or test data are required from our side to assist in the analysis.

 

Thank you for your support.

5 replies

mƎALLEm
Technical Moderator
December 26, 2025

Hello,

You could be facing EMI or EMC issues. But you forgot to attach the schematics.

Better to attach the complete schematics instead of the reset part.

"To give better visibility on the answered topics, please click on ""Accept as Solution"" on the reply which solved your issue or answered your question."
AditechAuthor
Associate
January 1, 2026

STM32G070CBT6 Reset section (2).png

Hello Find the attached reset circuit that we have used.

TDK
Super User
December 26, 2025

Read the RCC_CSR register to understand why the chip is resetting. Possibly a power issue. Ensure 0.1 uF cap is on NRST line.

"If you feel a post has answered your question, please click ""Accept as Solution""."
gbm
Principal
December 26, 2025

My wild guess: insufficient separation between the relay drive and MCU power supply and/or incorrect PCB routing. Impossible to evaluate without schematic.

My STM32 stuff on github - compact USB device stack and more: https://github.com/gbm-ii/gbmUSBdevice
STOne-32
Technical Moderator
December 28, 2025

Dear @Aditech ,

I have seen in few cases, Watchdog is active either by options bytes or by software and not refreshed properly during execution and so reboot the system. 
Hope it helps ,

STOne-32

gbm
Principal
January 1, 2026

And what happens if you remove R59? If the behavior doesn't change - see my previous post.

My STM32 stuff on github - compact USB device stack and more: https://github.com/gbm-ii/gbmUSBdevice
STOne-32
Technical Moderator
January 1, 2026

And also to remove R4 - 10K resistor .