Suggestions for 1 Digit LCD display?

Forum 2005-2010 (read only) General Frequently-Asked Questions
#1

Hi, I’m working on a project to display what gear a bike is in. I have it working fine with an LED but I’d like to use an LCD for greater outdoor readability. I really just need a single, decent size, digit and the simpler the interface the better. It will have to end up in a waterproof case with an RBBB or similar.

I see the Nokia 3310 from sparkfun, they also have a couple of new, cheap cellphone displays but i’m not sure of whether there’s logic with them. They have a new Nokia color LCD but again I’m not clear on the controller.

I am working with sensors from bicycle computers which have LCDs with a 19 conductor ribbon cable but my understanding is that the raw LCD requires fancy AC to drive it and it’s probably beyond me.

Any suggestions?

#2

Simple, raw LCDs are not that hard to drive. You don’t need an AC supply, because you can generate one with an EXOR gate. Feed a clock of suitable frequency to the backplane of the LCD and to one input of the EXOR gate. Then drive the segment from the output of the EXOR gate (do this for all seven segments). Then sending TRUE to the other EXOR input will drive the segment with a square wave in anti-phase to the backplane, i.e. effectively and AC drive.

#3

thank you, good to know. I’d still rather get something with connectors etc.

#4

You can get push buttons with built in LCD graphics displays:-

http://www.directindustry.com/prod/nihon-kaiheiki-industry/smart-push-button-switch-with-graphic-display-30967-369128.html

#5

thanks for the suggestions and info. I’m poking xors at the salvaged lcds and i’ve ordered a nokia 3310 display along with a 5V character display from seed as well.

#6