MOSFET Question Help

Discussion in 'Homework Help' started by d3ck, Feb 16, 2014.

  1. d3ck

    Thread Starter New Member

    Jul 14, 2013
    8
    0
    [​IMG]

    [​IMG]

    Question ask me to find ro and gm. But the problem is I need to find ID first.
    My guess to answer this question by doing KVL, VDD - VDS - IDQ(RS) = 0.
    From this I know VDS and I know the region is saturaion region.
    I use saturation region formula to find ID where I assume VGSQ = VGS.
    Am I correct by doing this. Thanks
     
    Last edited: Feb 16, 2014
  2. WBahn

    Moderator

    Mar 31, 2012
    17,757
    4,800
    It would be really helpful to have a circuit to refer to.
     
  3. d3ck

    Thread Starter New Member

    Jul 14, 2013
    8
    0
  4. anhnha

    Active Member

    Apr 19, 2012
    774
    48
    Just a learner.

    As I know, gm and ro is only depend on DC parameters such as VGSQ, VDSQ and IDQ and all these parameters are given.
    From VDD - VDSQ - IDQ(RS) = 0, you can find out VDSQ and check if it is in saturation.
    All you have to do is substituting these given DC operating parameters into the formulas for gm and ro.
     
Loading...