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2.8" Cap TFT Shield (1947) Powered by 3.3? Not Working.
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2.8" Cap TFT Shield (1947) Powered by 3.3? Not Working.

by BasitMustafa on Sat Sep 26, 2020 5:35 pm

I am trying to use this board with a non-Uno form factor board. In terms of data/functionality I have gotten this product working with a 3.3V board in terms of logic no problem, BUT I can't get it to work off 3.3V power. Setting IOREF, AREF, everything to 3.3V isn't working. It just won't power up. If I give it 5V on the 5V pin, no problem, but the logic levels are 3.3V, just 5V power. Looking at all the ICs on here, it seems like they're all 3.3V, I don't want to have to boost to 5V just to downreg to 3.3V on the board, how do I get this board to just run 3.3V from the 3.3V pin?

BasitMustafa
 
Posts: 4
Joined: Wed Sep 23, 2020 7:58 pm

Re: 2.8" Cap TFT Shield (1947) Powered by 3.3? Not Working.

by BasitMustafa on Sat Sep 26, 2020 6:58 pm

It actually seems that it is "working", but the backlight is only on/working when the 5V pin has power....what seems to be my mistake here?

BasitMustafa wrote:I am trying to use this board with a non-Uno form factor board. In terms of data/functionality I have gotten this product working with a 3.3V board in terms of logic no problem, BUT I can't get it to work off 3.3V power. Setting IOREF, AREF, everything to 3.3V isn't working. It just won't power up. If I give it 5V on the 5V pin, no problem, but the logic levels are 3.3V, just 5V power. Looking at all the ICs on here, it seems like they're all 3.3V, I don't want to have to boost to 5V just to downreg to 3.3V on the board, how do I get this board to just run 3.3V from the 3.3V pin?

BasitMustafa
 
Posts: 4
Joined: Wed Sep 23, 2020 7:58 pm

Re: 2.8" Cap TFT Shield (1947) Powered by 3.3? Not Working.

by BasitMustafa on Sat Sep 26, 2020 7:00 pm

Alright, well, managed to figure it out, just gave it 3.3V into the 5V pin and the backlight is on/working!

Going to leave this thread where I speak to myself there in case anyone else has this issue.

BasitMustafa wrote:It actually seems that it is "working", but the backlight is only on/working when the 5V pin has power....what seems to be my mistake here?

BasitMustafa wrote:I am trying to use this board with a non-Uno form factor board. In terms of data/functionality I have gotten this product working with a 3.3V board in terms of logic no problem, BUT I can't get it to work off 3.3V power. Setting IOREF, AREF, everything to 3.3V isn't working. It just won't power up. If I give it 5V on the 5V pin, no problem, but the logic levels are 3.3V, just 5V power. Looking at all the ICs on here, it seems like they're all 3.3V, I don't want to have to boost to 5V just to downreg to 3.3V on the board, how do I get this board to just run 3.3V from the 3.3V pin?

BasitMustafa
 
Posts: 4
Joined: Wed Sep 23, 2020 7:58 pm

Please be positive and constructive with your questions and comments.