Connect with us

Building a LCD 7 segment display watch from scratch

Discussion in 'General Electronics Discussion' started by hawx79, Aug 3, 2017.

Scroll to continue with content
  1. hawx79

    hawx79

    1
    0
    Aug 3, 2017
    hi,

    I am trying to build a small wrist watch from scratch for my friend. I don't know much about electronics, but I am pretty handy when it comes to figuring stuff out.

    What I would like to know is the parts needed to make a watch and a little bit of an explanation of how they work.

    I know I need a quartz oscillator, but I want to go with a MEMS oscillator. I have no idea how they work though.
    I bought a small LCD 7 segment display, here is the data sheet http://www.mouser.com/ds/2/244/LCD-S401M16KR-81359.pdf

    I would like the watch to be no bigger than the screen if possible, with all the electronic bits underneath the screen.

    Thanks for all your help

    sorry if i have no idea what I'm doing
     
  2. kellys_eye

    kellys_eye

    4,275
    1,146
    Jun 25, 2010
    You will need the control electronics, presumably a small processor, that can do the timing and drive the display plus any other 'housekeeping' functions. This will mean researching for the right device that has:

    the correct supply voltage requirement (usually around 3V)
    low power consumption - or an ability to switch to a power-down(saving) mode
    enough ports to drive the display and 'read' the buttons used to access it

    Getting the right device in a surface-mount package (tiny) won't be too difficult these days but sometimes the task of working with such incredibly small parts is beyond the 'physical' (not mental) capabilities of many. You're potentially looking at parts with a pin pitch of 0.4mm (or less) and 'pins' that don't actually exist - they are often 'pads' that require specialist soldering techniques to mount.

    Whilst many people have succeeded in building such watches (check out the Hackaday and similar sites) you may be better off 'copying' a design as doing it from scratch is no mean task.
     
  3. BobK

    BobK

    7,682
    1,687
    Jan 5, 2010
    Just driving that kind of display is a non-trivial project. Bare LCD displays, like the one you have selected, require an alternating voltage on the segment pins. There are PIC microcontrollers that have LCD display drivers built in. To do with software on a microcontroller that does not have them would be complicated.

    Hopefully, you have at least some programming experience.

    Bob
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-