run an 5v hd44780 compatible LCD with 3,3v?


I got a bunch of hd44780 compatible LCDs which are designed to run on 5v. I’d like to use them with an 3,3v arduino clone. It seems the logic takes the 3,3 v without a problem, but the characters are barely visible because the 3,3 v are not enouth for readable contrast (you got to tie pin 3 to ground for contrast)

What would be an easy solution for this problem? I don’t want to get 3,3 v displays because I’d like to use the one I have and besides that their orange is so beautiful :wink:

any hint is very appreciated :slight_smile:

A link to the datasheet would be helpful.

(you got to tie pin 3 to ground for contrast)

Normally you feed pin 3 with a small positive voltage via a potentiometer. Does this mean that you haven’t used a potentiometer or that the setting that gives 0V at the contrast pin is the best? You could try a slightly negative contrast voltage.