Why Totem Pole Circuit Used ?

Discussion in 'General Electronics Chat' started by mushahid980, Oct 3, 2010.

  1. mushahid980

    Thread Starter New Member

    Mar 6, 2009
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    My Question is just to know Why Totem Pole Circuit Used ? in Amplifier Circuits
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    Care to show a schematic?
     
  3. Audioguru

    New Member

    Dec 20, 2007
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    An audio power amplifier applies a positive voltage at a high current and a negative voltage at a high current to a low resistance speaker. So the upper transistor (NPN) in the totem pole pulls the speaker positive then the lower transistor )PNP pulls the speaker negative.
     
  4. tom66

    Senior Member

    May 9, 2009
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    A totem pole circuit is where an NPN transistor is put in series with a PNP to form a dual-rail amplifier, right?
     
  5. Wendy

    Moderator

    Mar 24, 2008
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    My first encounter with the term was with TTL. I lifted this off of Wikipedia.

    [​IMG]

    I think the term has expanded somewhat, for any output using two transistors, usually (but not inclusive) being the same type. The LM555 for example has an output that looks a lot like this, and I've heard it called totem pole:

    [​IMG]

    I think the term has gotten looser over time, but basically it is two transistors that connect the output to the power supply rails, but is not rail to rail. I would not class the boosters shown on the second half of the above picture as totem pole, though it could be argued.
     
  6. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    Totem pole are used in TTL chips only

    In Amps, they are refereed as push pull stage or class AB amplifier
     
    Last edited: Oct 3, 2010
  7. marshallf3

    Well-Known Member

    Jul 26, 2010
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    Think of the origin of the phrase = "things stacked upon another"

    You can just as well totem-pole resistors or coils (chokes, inductors) ....
     
  8. Ron H

    AAC Fanatic!

    Apr 14, 2005
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    I agree with this.
     
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