1. Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
    Dismiss Notice

Display Multiplex timing

Discussion in 'Microcontrollers' started by olly_k, Jul 6, 2003.

  1. olly_k

    olly_k Member

    Joined:
    Jul 5, 2003
    Messages:
    236
    Likes:
    1
    Location:
    UK
    I am about to start a project which involves multiplexing leds and displays. I want to use a fixed time period, but delay (PWM if you like) the 'on' time of the displays to get an adjustable output. Does anyone have an idea on the timing required to overcome persistance of vision? I figure it's got to be above say 50 or 60Hz tellies use this but the phosphors glow for somtime after further reducing flicker.
    Any ideas?
     
  2. TheAnimus

    TheAnimus New Member

    Joined:
    Jun 22, 2003
    Messages:
    116
    Likes:
    1
    Location:
    England
    hey i did a project where i was controlling the brightness of 8 LEDs using them as indicators, i had to use a capacitor in order to get a low brightness without the pulsing showing. (that was at 307.54hz approx)
     
  3. olly_k

    olly_k Member

    Joined:
    Jul 5, 2003
    Messages:
    236
    Likes:
    1
    Location:
    UK
    Thanks for that, I think I will get a 556 and mess about abit - thought about programming a pic with a test routine but this way I think will prove the point!
     

Share This Page