Coin cell to VBAT pin on a Nucleo board?

[john doe]

Posted on November 20, 2017 at 22:35

On a Nucleo board, is it as simple as pulling the 0 ohm resistor off SB45, and connecting a coin cell [something like a CR1220] to pin33 [VBAT] and ground, in order to have battery backup for the RTC registers?

[Zt Liu]

Posted on December 05, 2017 at 06:52

Sure!

I've done it many times on my F4 Nucleo boards.

Here my VBAT is Pin1!