Nucleo L476RG External power

[Claire2]

Hello,

I have a Nucleo L476RG that I plug onto a PCB that I designed (used as a power input) and to my computer (only used for data transfert).
My issue is that I would like to plug both to the Nucleo, but only use the PCB for its power supply.
Moreover, I don't want the Nucleo to power the PCB nor the computer to power either of them.
Could you please help me on this topic?
Thanking you in advance for your consideration.

Best regards,

Claire

[Melc_dB]

Hello @Claire2,

Please look at the user manual section 6.3 Power supply and power selection.

If you remove jumper JP5 or put it in position E5V (depending on the way you power application from your custom PCB), the STlink should not power nor the STM32 and the PCB.

However, verify that your PCB does not use the U5V pin.

Also the looking at the board schematic may help you: https://www.st.com/en/evaluation-tools/nucleo-l476rg.html#cad-resources 

Hope that will help you,

Best regards,

Melchior