I'm trying to fix broken Digispark (clone)...

Hi @mixza-81,

   As with many things in life, when you can't find anyone who has actually done the same before, sometimes you just have to try it and hope  ... and maybe this is one of those cases, as I have never seen one of these boards, the best I can do is look at the evidence on the web and add a little imagination.

I found a schematic at https://s3.amazonaws.com/digistump-resources/files/97a1bb28_DigisparkSchematic.pdf

which I 'assume' matches your board, and it shows each of the two data pins having a 3.6V zener to ground. (Confusingly, it shows the USB pins in the wrong order ... but never mind.)

So I think these zeners are to protect the analog inputs to the microcontroller, which seems reasonable.

So whilst I take no responsibility, if I were you, I would try the replacement you suggest. It is possible, but fairly unlikely, the microcontroller input has already been damaged by static, etc.

Of course, make sure you solder it in the right way round!

Good luck. Dave

Hi @davee.

Thanks for the reply.

I have bought several Digispark clones (always from the same Ebay seller) and I have noticed that the latest ones have a difrent in color of the LEDs and little thinner PCBs. Those broken Digisparks - all older versions - will stick tighter to a computer's USB port, and it's important feature, especially when Digispark is connected to a thick front panel, for example in NUC - like I've done... It’s the biggest reason why I’m trying to save these and not just switch to a new one. I got that my own Digispark case modeled so that it does not affect the operation of the USB connector.

That replacement Zener doesn't seem to do any harm when installed ... I hope it also does its job of protecting (like you said).

Hi @mixza-81,

  Thanks for the feedback - good to hear that you have been successful. I always like the principle of fixing something when the fault only concerns a tiny part of an otherwise complete and useful item.

I hope the Digisparks continue to give good service.

Best wishes, Dave