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Calculate Gate Source, Drain Current, and Source Voltage of a JFET

  1. Nov 29, 2013 #1
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
    So what I started with is Vg=(R2/(R1+R2))Vdd - 10 = -7 Volts this is incorrect though I was told it is -4 V what did I do

    Attached Files:

  2. jcsd
  3. Nov 29, 2013 #2
    Theoretically after I solve for this I would get Kn and Id. Then I would set up an equation to find Vgs.
  4. Nov 29, 2013 #3


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    The voltage across the potential divider R1+R2 is 20V. So the voltage across R2 is..

    20 * R2/(R1+R2) = 6V

    So the gate is 6V above the -10V rail which is -4V.
  5. Nov 29, 2013 #4
    Thanks man
  6. Nov 30, 2013 #5

    rude man

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    What equation were you given that includes ka', W/L and Ka? These are not standard terms in a JFET model so you need to give us your equation(s).
  7. Dec 4, 2013 #6
    Oh yah I got it all figured out man thanks just had the test too hope I did well
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