Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

JFET amplifier

  1. Oct 21, 2005 #1
    Does anyone know the purpose of the capacitors circled in red in the file attached? What are their functions in the circuit? Thanks!

    Attached Files:

  2. jcsd
  3. Oct 21, 2005 #2
    The capacitor allows the AC signal to pass, but blocks the DC bias voltage established by resistors so that any preceding circuit is not affected by it.
  4. Oct 21, 2005 #3


    User Avatar

    Staff: Mentor

    And the 4.7uF capacitor increases the gain above 66Hz. The source resistor in parallel with that cap is used to set the DC bias point more accurately.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: JFET amplifier
  1. JFET question (Replies: 5)

  2. 2 Stage JFET amplifier (Replies: 3)

  3. Clarification on JFET (Replies: 1)