need help about 555 timer..

Discussion in 'General Electronics Chat' started by harikanaidu, Mar 22, 2016.

  1. harikanaidu

    Thread Starter Member

    Nov 28, 2014
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    555 monostable.jpg Hi, I want to design adjustable timer for my application..I am using a 555 timer for that purpose.can a 555 timer drives the relay directly if i connect the 555 in monostable mode and relay at the ouput of the 3rd pin of 555..
     
  2. #12

    Expert

    Nov 30, 2010
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    It depends on which model of 555 chip and how much current the relay needs.
    You did not tell either of these.
     
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  3. DickCappels

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    Aug 21, 2008
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  4. harikanaidu

    Thread Starter Member

    Nov 28, 2014
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    thankyou so much
     
  5. harikanaidu

    Thread Starter Member

    Nov 28, 2014
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    I am using NE555 timer..and relay used is 12v relay
     
  6. harikanaidu

    Thread Starter Member

    Nov 28, 2014
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  7. #12

    Expert

    Nov 30, 2010
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    The NE555 can supply 200 ma but you did not tell the current your relay uses. You told the voltage.
     
  8. DickCappels

    Moderator

    Aug 21, 2008
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    Not all '555's are of the same design. Some might be more sensitive to this reverse current flow than others. As I recall, the original intersil application booklet indicated that this diode is a good idea for their (original) version of the NE555.
     
  9. harikanaidu

    Thread Starter Member

    Nov 28, 2014
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    Relay
    This is the 12v relay i have...Input current required by it is not mentioned
     
  10. harikanaidu

    Thread Starter Member

    Nov 28, 2014
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    Can you just tell me what are the other version of 555 other than NE555..
     
  11. #12

    Expert

    Nov 30, 2010
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    Lm555, TLC555, SE555, ICM7555, and a few others.
     
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  12. harikanaidu

    Thread Starter Member

    Nov 28, 2014
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    Can you please tell me how to know the current required by the relay...It is not present in the datasheet even
     
  13. #12

    Expert

    Nov 30, 2010
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    Try Google 12V 0.36W 30ma
     
  14. wayneh

    Expert

    Sep 9, 2010
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    Look harder (elsewhere, Google is your friend). It's a 400Ω coil in the 12V version.

    Here.
     
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