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555 Timer

  1. Nov 1, 2006 #1
    Hi, I have a 555 timer IC. For my work, my colleague asked me to make it so it can output 100 KHz frequency. (astable)

    My Ra = 6.8 kOhms and my Rb = 4.7 kOhms...

    I know that the Frequency = 1 / (T_high + T_low) where

    T_high = 0.693(Rb + Ra) * C
    T_low = 0.693(Rb) * C

    Although I'm not too sure what to do from there.

    Any help?
  2. jcsd
  3. Nov 1, 2006 #2


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    Staff: Mentor

    Do you have the datasheet with the design guidelines? That's the best place to start. If you have specific questions about the datasheet's guidelines, can you post a pointer to the datasheet, and I'll take a look.
  4. Nov 1, 2006 #3


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    Science Advisor
    Gold Member

    Does http://www.doctronics.co.uk/555.htm#astable%20components" [Broken] help?
    Last edited by a moderator: May 2, 2017
  5. Nov 1, 2006 #4
    I got it, nevermind. Thanks though :)
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