STM32F103 Reduce VBAT Current

[nmamore]

My datasheet (STM32F103VC) states the Vbat current draw is 1.4uA. Is there a way to reduce this? I only need the backup domain for RTC/LSE. I know there are many backup registers as well. Could I turn these off to reduce current draw?

[TDK]

The backup domain cannot be partially disabled.

[nmamore]

Thank you. Are you familiar with any possible ways that I could further reduce current draw?

[TDK]

You could reduce the voltage to the minimum allowed. I don't think there's anything else you can do apart from that, but I'm not an expert in low power applications.

Logically, if there were something easy that could be done to reduce the current, it would be silly of them not to use the lower value in the datasheet.

[waclawek.jan]

Use a different STM32 model, e.g. 'L4 - you can have mostly pin and function compatibility and roughly 2-3x lower IVBAT.

Most of the current goes to LSE/RTC. For even lower battery consumption use a well-chosen external RTC.

JW