Running Nucleo WB55 off a 3.7V LiPo battery

[NicRoberts]

Nucleo-WB55RG

The docs mention that it can be run off a button cell & also mention that the 3V3 pin can be used to power the board. 

Is it possible to run the board off a 3.7V LiPo battery? 

My application is pulling 7ms & using BLE

[Andrew Neil]

Take a look at the schematics - see if there is a suitable regulator ...

As always, the schematics will be available on the 'CAD Resources' tab of the Product Page:

https://www.st.com/en/evaluation-tools/nucleo-wb55rg.html#cad-resources

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@NicRoberts wrote:

My application is pulling 7ms & using BLE

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you mean 7mA ?

PS:

See also the Power Tree diagram in the User Manual:

https://www.st.com/resource/en/user_manual/um2819-stm32wb-nucleo64-board-mb1355-stmicroelectronics.pdf#page=12

via: https://www.st.com/en/evaluation-tools/nucleo-wb55rg.html#documentation

From that, you'd need to be looking at the specs for U3 ...

[NicRoberts]

Yes sorry, I meant 7mA not ms.

Looking at the power tree diagram you provided (which oddly I cant find in my copy of the User Manual), I would need to close SB28, remove all the jumpers from J1 & make sure SW5 was in the right position? 

I can find SB28 but I cant find CN4 or SW5 on my board.

I did find the jumper & SB configuration table though (see below), which implies that I need to close SB27 and keep SB28 open? Still no clue where CN4 is though...<<< OK found it now

[AScha.3 · Accepted solution]

NO ! You not on 3.3V supply !  

You want use a LiPo as source, so it has 3.0 ... 4.2V .

You have to use the 5..7V INPUT setting, SB28 closed.

[NicRoberts]

So the above selection then, that is not clear in the docs at all.

[AScha.3]

Right. 5..7V range

[Andrew Neil]

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@NicRoberts wrote:

So the above selection then, that is not clear in the docs at all.

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Looking at the schematics is probably the easiest/safest way ...