Mesa 7i77 output

Tom_R2E3 wrote: Hi.

I power cycled the PC and machine this morning, but sadly nothing changed. As soon as I power the machine on I get 24v on the output pin of the 7i77. I think I have damaged it.

you get 24v only on the one output? all the others are ok? If so, switch outputs and declare that output defective.

Check your relay, maybe it has failed in some way or your wiring might have a short somewhere that it is killing your outputs.

If you have a bad driver output, the whole NCV7608 chip
has got one foot on a banana peel, best to replace it

You should also check carefully if any other loads on that
chip could be missing flyback diodes, I dont think EMI
could damage a driver chip unless it was pretty horrendous

That terminal shows a diode is internal to the terminal from what I see.

I have some outputs on my VMC that energizes a relay and I have diode on it, and when I release the relay, the 7i77 locks up and i have to cycle power. I put snubber circuit on the contact side of the relay and it fixed the issue. It is however a highly inductive load and I am probably lucky the 7i77 lived through it.