About Transistors conducting

Discussion in 'General Electronics Chat' started by TheDag, Feb 12, 2012.

  1. TheDag

    Thread Starter Member

    Jan 1, 2010
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    Hi,
    Does between the emitter and collector have any conducting while its idle???

    Thanks.
     
  2. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Are u on some kinda medication ?
     
  3. nerdegutta

    Moderator

    Dec 15, 2009
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  4. TheDag

    Thread Starter Member

    Jan 1, 2010
    94
    1
    Medication? No.
    Please more answers...
     
  5. tom66

    Senior Member

    May 9, 2009
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    To answer your question, yes, there is a small amount of leakage current when the transistor is off.
     
  6. Wendy

    Moderator

    Mar 24, 2008
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    It can be very small however. Small enough to treat as an open switch.

    When discussing transistors it is important to remember there are several families. I assume you are talking BJT in this case, given you mentioned Collector and Emitter.

    The early transistors, made from germanium, were much worse. The new ones are much better. BJTs are fundamentally analog devices, even if they can be run in their digital regions. Something to remember.
     
  7. TheDag

    Thread Starter Member

    Jan 1, 2010
    94
    1
    Im talking about BC547 and BC557..
     
  8. Audioguru

    New Member

    Dec 20, 2007
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    Usually a transistor is turned off by something connecting its base to its emitter, maybe a resistor. Without something between the base and emitter then a very small collector to base leakage current is amplified by the transistor and it conducts much more current than with something connecting its base to its emitter.
     
  9. TheDag

    Thread Starter Member

    Jan 1, 2010
    94
    1
    Thanks everyone, I Think I Got it...
    If you have more information please tell me, Thanks.
     
  10. Wendy

    Moderator

    Mar 24, 2008
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    Just curious, are you going to school, or are you self taught? I was messing with electronics many years before I went into college. I had holes in what knew until a more formal education.

    But I still had fun. I was even etching my own boards.
     
  11. TheDag

    Thread Starter Member

    Jan 1, 2010
    94
    1
    Hi,
    I am not learning electronics....
    BTW, Im etching PCB also :)
    With Toner Transfer method, or free drawing with marker....
    BTW, Its great forum, fast answers, and very good people....

    Thanks.
     
  12. Wendy

    Moderator

    Mar 24, 2008
    20,766
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    With questions like that you are. :D :p

    This is OK, we like questions, and no one is born knowing this stuff.

    I assume you've seen this article?

    How I make PCBs
     
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