How it work

Discussion in 'General Electronics Chat' started by TAKYMOUNIR, Jul 25, 2012.

  1. TAKYMOUNIR

    Thread Starter Active Member

    Jun 23, 2008
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    In this circuit i use hcpl 3180 i use 2 in series in my circuit i know that the minimum current for hcpl 3180 to turn on is 10 ma so how this circuit work(if=10ma)
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    Not sure where you got your information about LEDs, but it is wrong. An LED will light with 0.0001 amps, 0.01 (10ma) is the rated current.
     
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  3. praondevou

    AAC Fanatic!

    Jul 9, 2011
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    According to figure 15 of the datasheet the minimum forward current for turning on the output is 3mA.
    10mA is the recommended forward current.
     
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  4. TAKYMOUNIR

    Thread Starter Active Member

    Jun 23, 2008
    351
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    what is the function of R2 IT JUST LIMIT THE VOLTAGE OR WHAT
    THANKS
     
  5. praondevou

    AAC Fanatic!

    Jul 9, 2011
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    I don't think it's really necessary. Where does this circuit come from?
     
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  6. Jony130

    AAC Fanatic!

    Feb 17, 2009
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    It looks like R2 limits the diode reverse breakdown voltage.
     
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