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PMOS Working Concept

  1. May 14, 2009 #1
    I believe that to make a PMOS work, Vgs (th) needs to be negative but when I give -5V to source and connect it in a source follower mode i.e. vg = -5V, I do get an output.
    Can anyone tell me how and why?

    - Hemant
  2. jcsd
  3. May 14, 2009 #2


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    1. Can you post a circuit diagram.

    2. Can you make it clear whether you are using mosfets or jfets.
    Last edited: May 14, 2009
  4. May 20, 2009 #3
    I have attached a sample PMOS circuitry that I have simulated. I am actually using a PMOS FET.

    Attached Files:

    • PMOS.JPG
      File size:
      29.2 KB
  5. May 21, 2009 #4
    Thats because you shorted the gate and the source together. They are tied to -5 Volts with respect to ground but not -5 volts with respect to source.
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