LCD to LED or LED meters.

silvertoy · 02-17-2003, 12:05 PM

Hello everyone, I've been browsing here for a while but decided I needed to make a post so I finally signed up (so yes, I'm a noob). This doesn't necessarily pertain to LCD displays in the video sense but on a more rudimentary level of simple clock-type displays.

I would like to create a few devices for my car, a digital voltmeter to measure my batteries output, a digital temp gauge to monitor several different thermocouples throughout the vehicle and lastly a clock

I know I can purchase many of these items separately but I have more time than $$$. Plus many of these items come with odd displays from analog to indiglow LCD's. What I want to use in place of these LCD's are very small, red, 7-segment LED's which I know how to easily obtain. I would like all of these items to be the same display type for aesthetic purposes.

I can dissasemble a cheap digital multimeter for the purpose of the voltmeter, however they have LCD displays and I need red 7 segment LED's. Does anyone have any experience with how to do this or maybe have some resources they could point me towards to get me started.

The same goes for the clock, and the temp gauge, I can get a combination clock/indoor outdoor display for $15, but it has an LCD display and I need LED.

I will mount all of these 7-segment LED's in a special place on my dashboard, all near one another. Any help would be appreciated, and if the mods feel this belongs somewhere else, then I won't be offended if it gets moved.

It would be simplest and cheapest to re-use these readily available devices and just change thier display, but if that isn't possible due to the IC type, then I may go the route of building these items from scratch. In which case I will need a lot more help.

Thanks and I hope to have a good time on here and even make some positive contributions.

Alphared · 02-17-2003, 03:19 PM

well you need a decoder IC to take the reading and convert it to numbers. Check to see if you can use the chip that drives the voltmeter's LCD. From there you have to figure out what the pin outs are.

I forgot what IC you would need cause I only did it once in class, and you might have to look at some electronic stores to find it, not sure radioshack carries it anymore.

silvertoy · 02-17-2003, 08:43 PM

So are the inputs to the LCD's the same as the inputs to the LED's I just need to re-wire them or is it one chip/one connection?

Charliey · 02-17-2003, 11:07 PM

Try taking a look through http://www.qkits.com/serv/qkits/qkitscat/catalog.asp

they would most likely have some kits which would be easier to reverse engineer to add LEDs to then prepackaged items.