custom PCB(ATMEGA328P/Arduino pro mini ) run with coin cell issue

Hello,

I’m working on one of the project and its board MCU is ATMEGA328P.

When I’m run on coin cell with custom PCB then MCU will be restart again n again.

When I’m run on Li-ion battery its code and MCU working very well.

So, please tell me the issue and suggest me the test case for overcome this issue.

Thank you.

Regards,
PRATIK

What's your BOD set to?

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