Rgb LCD issue
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Rgb LCD issue

by Derkatwork on Sat Mar 23, 2013 10:15 am

I have a rgb LCD and applied +5v to pin 15 and ground to the last three pins (16-18). The backlight won't come on any advice?

Note:red is ground from arduino, green is +5v to pin 15, orange is pins to ground.

Thanks for helping.
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Re: Rgb LCD issue

by pburgess on Sat Mar 23, 2013 11:41 am

Fix is below. But don't do this until you've added current-limiting resistors for the backlight! Anywhere from 220 Ohm to 1K should suffice. Failure to do this will burn out the LEDs pretty quickly.

On long breadboards like that, the power rails aren't continuous down the whole length. See the slightly longer gap in the middle? Put jumper wires across there, or just move the +5V across that space.
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