Author Topic: MightyHat backlight not on [solved: check solder joints]  (Read 2041 times)

hickse

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MightyHat backlight not on [solved: check solder joints]
« on: June 09, 2019, 01:17:44 PM »
I have a MightyHat on a Raspberry Pi Model 3 A+, but the backlight does not stay on. The R2 general purpose pushbutton does momentarily flash the backlights as it is cycling thought the LCDlight percentage menu, but I can't figure out how to keep the backlight on.
Any help would be really appreciated. 
« Last Edit: June 11, 2019, 09:12:41 AM by Felix »

Felix

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Re: MightyHat backlight not on
« Reply #1 on: June 10, 2019, 07:07:00 PM »
That should keep it on at whatever percentage the LCD shows.
It's just a PWM signal from D3 to the LCD backlight.
I would check any solder joints on the LCD header, maybe some DMM continuity check from the atmega pin to the LCD backlight. See the schematic.

hickse

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Re: MightyHat backlight not on
« Reply #2 on: June 10, 2019, 10:12:56 PM »
Thank you Felix, Your suggestions worked.  It had a bad solder connection on the LED pin.