Public Service Announcement: TRIPLE-CHECK polarity!!
The FCs currently shipping have the 5V-out plug now with correct polarity!
We install the plugs flipped. Thats not ideal because the plug isnt symmetric, but it works. The next batch of PCBs will have the traces reversed, so we can install the plug in the right orientation and right polarity.
If ever in doubt, check the polarity indication on the bottom of the board.
A little side story while Im at it:
I have a set of Plantronics W720 wireless DECT communication headphones.
Very top of the line, love them. Have cost a fair penny. Battery last for around 8 hours. Still, one day I run out of battery and want to keep talking.
So I open it up to check what battery is in there, and see a 1S lipo with Micro-JST-plug. Yeah, lets just stick a Nano-QX battery in there, that will do!
Hmm… light do not go on, whats happening? SMOKE, SMOKE, pull the plug!
A lot of smoke came out. Wrong polarity ;( Hundreds of dollars down the drain…
Just to check, I reverse the plug and put it back in.
Guess what: its still working!
I feel I have used up my luck and probably yours too.