Need help to make this 555 circuit

Discussion in 'The Projects Forum' started by mrghost, Aug 19, 2015.

  1. mrghost

    Thread Starter New Member

    Feb 4, 2011
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    Hi
    I want help to make acircuit to genetate a3 pulses then it turns off any idea?
     
  2. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    What do you mean, "to generate a3 pulses"? Is that a typo? Do you mean 3 pulses?

    What kind of timing between them? How long do you want the pulses to be? What voltage? What will it be used for?

    You're going to need to provide a whole lot more information than what you have given.
     
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  3. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    Info. a little sketchey but as a start: 555 pulse gen. feeding a ring counter, 4017 or 4022, when 3rd pulse rises, it is inverted & feed back to 555 reset, pin 4 which stops all operations until counter is reset. Output taken from 555-3
     
  4. ScottWang

    Moderator

    Aug 23, 2012
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    I want help to make a circuit to generate a 3 pulses then it turns off any idea?

    I think the TS need ne555 and CD4017 and some diodes and resistors, and it was almost like Bernard described.
     
  5. DerStrom8

    Well-Known Member

    Feb 20, 2011
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    I agree, I think a 4017/555 combo would be the simplest option, if all the OP needs is logic signals. He'll need to realize he won't be able to source a whole lot of current from the 555 though--he'll need a transistor and/or a relay as well. He'll also want to ensure that whatever he's driving won't interfere with the clock input of the 4017, since the output of the 555 goes to both the 4017 clock input and the TS's load. A transistor would definitely be a good option.
     
  6. mrghost

    Thread Starter New Member

    Feb 4, 2011
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    thank you for reply but there is a modification,
    i want to make a circuit that when it take permanent 12v volt it generate one pulse only so it produce one pulse only every time that i connect it to 12 volt source.
     
  7. ScottWang

    Moderator

    Aug 23, 2012
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    If you just want a trigger output a pulse then you can using one stage of npn bjt to inverting the input of ne555 monostable circuit.
     
  8. MikeML

    AAC Fanatic!

    Oct 2, 2009
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    167.gif
     
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  9. mrghost

    Thread Starter New Member

    Feb 4, 2011
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    Thank you very much, but I want a final modification, I want if the is a constant 12v it produce one pulse and when I disconnect the constant 12 volts it produce one pulse again and so on
    Any idea
     
  10. #12

    Expert

    Nov 30, 2010
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    ..........
     
  11. MikeML

    AAC Fanatic!

    Oct 2, 2009
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    What is the pulse powering? It makes a difference to the circuit required.
     
  12. #12

    Expert

    Nov 30, 2010
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    @mrghost
    Trying to drag the information out of you is called, "playing twenty questions" because that is the name of a child's game.
    Changing your requirements during every post is also difficult to cope with.
    Please present a reasonable request with the necessary information included, all in one post.
     
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  13. mrghost

    Thread Starter New Member

    Feb 4, 2011
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    I am very sorry for much questions
    But the modifications was appeared while working
     
  14. mrghost

    Thread Starter New Member

    Feb 4, 2011
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    The final requested circuit is when there is aconstant 12 volts from car battery it give one pulse and when disconnecting the constant 12 volts dc it gives one pulse again that's all
     
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