Rookie mistake... burned my MEGA regulator?

[joffers]

Hi -
After writing a lot of c++ mesh code it was time to take my 3 radios out for a multi-hop test. In a very late night, very rookie mistake I hooked up the power to one breadboard incorrectly and looked away. One tell-tale wiff had me saying; "oh sh*t, oh sh*t, no, no, no", but the damage was done - I *think*.

Question:
I'm up the challenge of repairing it if it's possible. Currently I can't get it (moteino mega) to reset or respond. Did I burn out a fuse? And if so can you tell me where it is and what it is so I might replace it? Hate to toss a perfectly good board if it can be repaired.

thanks!
--J

[syrinxtech]

AFAIK, there are no "fuses" or replaceable components on Moteino products.

If you let the smoke out it, most likely the device is toast.  If you connect power and can't at least run the "blink" sketch you can probably call it quits for that device.

[emjay]

@joffers,

With reverse polarity, if you are lucky, the LDO chip (MCP1703) sacrificies itself for the good of the rest of the board.  If you have a supply available of < 3.5v (two fresh AA in series will do at a pinch), remove the 3pin LDO and bridge across what was its IN and OUT pads, then see if you get a useful response with the test supply.

If not - aim it at the round bin and put that one down to experience.

[TomWS]

@joffers,

With reverse polarity, if you are lucky, the LDO chip (MCP1703) sacrificies itself for the good of the rest of the board.  If you have a supply available of < 3.5v (two fresh AA in series will do at a pinch), remove the 3pin LDO and bridge across what was its IN and OUT pads, then see if you get a useful response with the test supply.

If not - aim it at the round bin and put that one down to experience.

Good suggestion, emjay.  Further, @joffers, if you physically remove the MCP1703, you can simply wire the 2 AA batteries to the 3.3V pin.

Tom

[joffers]

@emjay, @tomws. Great suggestions, will give them a try and report back.
thanks!