bc108c Darlington Pair equivalent ? Is there one?

Discussion in 'The Projects Forum' started by Tony Spence, Jan 26, 2015.

  1. Tony Spence

    Thread Starter Member

    Dec 20, 2013
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    Hi there is does anybody know if there is an equivalent replacement to having two BC108C transistors in a Darlington pair in a circuit ?
     
  2. MikeML

    AAC Fanatic!

    Oct 2, 2009
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    Looks like a "nothing special" NPN to me. What is the application?
     
  3. Tony Spence

    Thread Starter Member

    Dec 20, 2013
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    I'm new to electronics but i managed to make a circuit from an existing LED chaser circuit with a few mods.

    I am trying to use the transistors as a current gain.
     
  4. #12

    Expert

    Nov 30, 2010
    16,262
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    Yes, a real Darlington transistor..but why spend a dollar when you can do it with a pair of 7 cent transistors?

    yeah, yeah, I know...you didn't get the deal I got at www.mouser.com :rolleyes:
     
  5. Tony Spence

    Thread Starter Member

    Dec 20, 2013
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    Thanks looks a bit complicated tho
     
  6. #12

    Expert

    Nov 30, 2010
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    OK. So buy a real Darlington transistor. Post a schematic and we'll help you get the resistors right.

    The, "c" version is the high gain selection, so you can't fake it with a different version. This will just have to be a Darlington.
     
    Last edited: Jan 26, 2015
  7. Tony Spence

    Thread Starter Member

    Dec 20, 2013
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    I Know that the BC108C has a current gain of 420 but in a darlington pair what is the current gain together?
     
  8. #12

    Expert

    Nov 30, 2010
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    usually around 10,000
     
  9. absf

    Senior Member

    Dec 29, 2010
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    Here's the pdf of MPSA13 & 14. The current gain is on page 2 as hFE.

    Allen
     
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