Digital LED clock

Discussion in 'The Projects Forum' started by meijaz, Dec 11, 2009.

  1. meijaz

    Thread Starter Member

    Nov 20, 2009
    I am working on a simple project of making digital 7-segment led clock using a IC i.e. LM8360.

    Everything is working fine. But I have two questions:

    1. I am using 470 ohm resistor with 12 V supply for the LED display. My problem is that when there are less segments glowing they become bright and vice versa (when there are more segments glowing it becomes overall dim). I want all the segments glow with same brightness. I am using MAN8940.

    2. Moreover, my next project is to use large seven segment displays which this IC can not drive. Please tell me a simple method to use this IC to drive large LED display.

    Thank you.
  2. eng1ne


    Dec 4, 2009
    Replace the 470R resistor with a 470R on each for each segment. Presently, you are limiting the current for all the segments to a total of 25 mA which is being distributed uniformly across them all. Each segment alone has a maximum forward current of 30 mA.

    Secondly, what are the seven segment displays you intend to use for your next project? I would scrap the LM8360 if possible and find an IC with an English - rather than Chinese - datasheet.