ESP32-POE-ISO EXT 5V and USB. Is this possible with a USB Isolator?

[Dyslexicbloke]

Hi folks,
I have several ESP32-POE-ISO units and am working on a data logging application.

The system is powered by a 12V, nominal, LiFePo4 battery with the option to solar charge.The ESP32-POE-ISO has a LiPO connected and can charge its self when required.

I note from the documentation that USB and 5V power should not be applied at the same time. This makes development and particularly debugging a bit of a pain it also means that I MUST disconnect the USB after an upload before the EXT power is connected, again a bit of a pain.

If I use a USB Isolator, Like this, can I still read serial dfata when the EXT power is on?

[LubOlimex]

Your understanding of the board and the issue and the way you operate the board are correct. Disconnect external power, apply USB, debug (program, etc), disconnect USB, re-apply external power.

USB isolator should fix the issue. Hardware-wise the product you linked should be alright (ADuM3160 is well-known isolator chip). We have own USB-ISO with ADuM4160 (ADuM4160 is certified for 5kV and voltage range is a bit wider, while ADuM3160 for half of that - 2.5kV and narrower voltage range):

https://www.olimex.com/Products/USB-Modules/USB-ISO/

Notice that USB isolators like that only support low and full speed USB (no high speed or better), so there can be driver issues or USB speed limit.

[Dyslexicbloke]

Thanks, that is good to know...
Help much appreciated.