I am new to circuit design and debugging them. I have recently helped in building a PCB with certain kind of circuits on it which includes opamp, boost converter, microcontroller and accelerometer. The board is battery operated. It basically goes on a device which is supposed to be water proofed. But by any reason the water can go inside the device.
The circuit is works fine it draws minimal sleep current in micro amps when in sleep mode and set current when its measuring. But when the liquid(approximately a drop of liquid and it would have already dried up "the liquid is mostly sugary") gets into the board "the board still works it even measures" but it starts drawing more current. Hence the battery gets drained faster.
My question is
Can I debug the boards and bring it back to its normal working condition? If so how to debug it?
I have 4-5 boards which are in the same condition will they all have same problem if I debug 1 board?
It would be really helpful if I could get some help from this forum.
Thanks
Best Answer
First remove the battery if it's attached to this board. Bake them for about 30 minutes at around 40C-50C (maybe check data sheets for temperature ratings but this should be okay). This should remove any moisture. Let them cool down and then perform your current consumption and functional test again.
In the future, conformal coating should help if they aren't coated. Also, maybe seal up the enclosure better with some epoxy or silicone. You could also if there's a place/room add or zip-tie a moisture absorbing packet (silica gel) to the board. Water/moisture usually finds a way even if you don't think it's possible.