Hi Steve, it was mentioned here: Cage of Faraday for Up2Stream Mini ? - #6 by KolfMAKER But my board doesn’t have a jumper header in that position. Was there a revision at some point?
I’m using one of these https://www.digikey.co.uk/en/products/detail/recom-power/R-78C5-0-1-0/2652148
I have the I/C circuit on the input and a 10uf cap across the output as suggested in the datasheets.
If I power the Mini from this but connect the output to another amp then it’s fine…if I use it in the amp I’m building but power the mini from another source, then it’s also fine. Which is why I think I have some ground isolation issue…ordered an LC module but not convinced it’s going to help here.
To get the feed to my DC-DC converter the only supply available to me is one side of the ±25v supply on the amp board…so my supply ground is the centre (0V) rail and I suspect this is what is causing my ground isolation problem.
I also measured between AGND and GND on the mini when it’s disconnected and it appears to be a dead short (or a very small coil) which is why I was interested in that jumper mentioned in the thread.