Help needed to make a driver circuit for three large seven segment displays

[Ian Rogers]

Ian Rogers Where?

Yeah.. Sorry about that.... I meant to edit.. It was KISS... You know I'm loosing my marbles...

 

[KeepItSimpleStupid]

You know I'm loosing my marbles...

Most of the time you find them in the last place you look

 

[granddad]

Is April seven segment month .. or have i time warped back to 1980..

 

[gophert]

Is April seven segment month .. or have i time warped back to 1980..

Time for Senior Projects!

 

[schmitt trigger]

7 segment LED displays have this appealing retro look.

 

[Visitor]

When I did a project for the FAA (Federal Aviation Administration), I got a lot of pushback over my decision to use 7 segment LEDs over liquid crystal displays. "The look so much better and we can have fancy graphics. And they are so cheap!"

Yes, that's true. But the FAA is still using equipment from the 70s with no plan to replace it. This stuff I build may still be in use long after I care. I don't know how long a cheap LCD will hold up, and I don't know (and seriously doubt) any displays with the same driver chip and mounting dimensions will be available at any point in the future. By my calculations, based on expected use, my LED displays should work at a minimum of 15 years, and I expect 0.56" 7 segment displays to be around long after that, available from many different sources.