LED display issues

[HinesNetwork]

Hi all,

I'm hoping someone can point me in the right direction. My Whirlpool ovens display is going out. I thought it was the LED's actually failing but I removed the board and tested them and they work. When I put the board back in the oven the display started working again. However it started failing again (not sure of the actual time, but maybe an hour). I can only assume that disconnecting the power caused the microcontroller to reset. Does this mean the microcontroller is diving? Or is there something else I should be looking at?

Thanks,
Jason

[Andy Watson]

What test equipment do you have?
More information would be useful in making a diagnosis. But, taking a flying guess, I would guess that something is shutting-down due to thermal problems. Could be the display driver but more likely a voltage regulator. If it is the later it could be due to faulty caps across the supply (look for something(s) getting hot), or it could be due to reservoir caps drying out, or it could just be a faulty regulator.

[HinesNetwork]

I've got several DMMs, logic analyzer, scope (although I've been afraid to use it on this since it's powered by AC).

I suspect it's a thermal issue too. It's just strange that it worked after being disconnected for awhile. I saw no physical indications it was a bad cap. I should have some time to remove it and do some more testing tomorrow.

Thanks,
Jason