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Strange Nokia display runs without power  

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Peterthinks
(@peterthinks)
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Joined: 2 months ago
Posts: 9
2020-08-31 7:08 am  

I suspect it's because it is a 3.3 volt display but messing around with mine I added a potentiometer to the backlight and while moving wires around noticed it was still running. With no power supply! So I yanked the one going to the backlight. And the ground. Still runs! So I went from eight wires down to 5!

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Perfect is the enemy of good. Hotglue is not a crime!


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Peterthinks
(@peterthinks)
Active Member
Joined: 2 months ago
Posts: 9
2020-08-31 7:11 am  

If anyone has a way to measure current draw on a display like this running normally and running just on the logic power I am quite curious. Will this extend battery life?

Perfect is the enemy of good. Hotglue is not a crime!


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Peterthinks
(@peterthinks)
Active Member
Joined: 2 months ago
Posts: 9
2020-08-31 10:10 pm  

Well turns out this display is a Unicorn. I have five of them and only one has this strange ability to run without being hooked up to power. I tested the pins and nothing is shorted out. I tried jumping the digital pins to the VCC pin on another display but only succeeded in burning it out. Oh well. I labeled it "Unicorn" for further study in the future.

Perfect is the enemy of good. Hotglue is not a crime!


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