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Requirement of this resistor?

  1. Apr 26, 2015 #1
    The following circuit is a Vbe temp compensated circuit
    Query : what exactly the use of the 10k resistor required to connect the bases of two transistors....we can also have a direct coupling to connect the bases of both transistors....what exactly the difference it could make by adding the coupling resistor??

    sorry if Im being too vague..

    Attached Files:

  2. jcsd
  3. Apr 26, 2015 #2


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    There are several 10k resistors in the schematic. The resistor from the collector of Q1 to the base of Q2 sets the input impedance for the signal input. The resistor from the collector of Q1 to the base of Q1 is a feedback resistor that tries to keep the base of Q1 at the same potential as the base of Q2.
  4. Apr 26, 2015 #3
  5. Apr 26, 2015 #4
    Great explanation in post #12 of your mentioned thread...
    Ok here it think it..If we change the values of both base resistors..it would result in unequal Vbe for both transistors ..which would further vary both transitor's Vce resulting in difference in collector current of both transistor ....hence a kind of unequal compensation ....
    am i right?
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