generation of square waves

Discussion in 'General Electronics Chat' started by erkinkarahayit, May 9, 2009.

  1. erkinkarahayit

    Thread Starter New Member

    May 7, 2009
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    Hi everyone ı am working on my final project and I faced problem while getting square waves with 90 degrees of phase apart. Can you help me??
     
  2. Papabravo

    Expert

    Feb 24, 2006
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    You probably need to start with a circuit called an "astable multivibrator".
     
  3. Wendy

    Moderator

    Mar 24, 2008
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    Think two flip flop circuits, toggle them right and you have your answer.
     
  4. Papabravo

    Expert

    Feb 24, 2006
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    That's two steps and I think you have your answer
     
  5. Ron H

    AAC Fanatic!

    Apr 14, 2005
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    Look up "Johnson counter".
     
  6. Papabravo

    Expert

    Feb 24, 2006
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    A two stage Johnson Counter has a state sequence that goes
    00 -> 01 -> 11 -> 10
    which is just the thing you need, and can be built as a shift register. If the FFs have inverted outputs, then you don't even need an external inverter, but you still need a clock to make it work. That is where the multivibrator comes in.
     
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