1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: BJT Differential Amplifier

  1. Feb 28, 2016 #1
    1. The problem statement, all variables and given/known data
    diff amp.PNG

    Analyse the circuit to provide predictions for (a) the differential input resistance, (b) differential voltage gain, (c) single-ended voltage gain, (d) common-mode voltage gain, (e) common-mode rejection ratio (CMRR) in dB, (f) common-mode input resistance and (g) the single-ended output resistance. The common-mode gain may be calculated using the output admittance (hOE) in Fig. 6 in the CA3086 data sheet. [ro = 1 / hOE].

    2. Relevant equations

    3. The attempt at a solution

    For a) is the differential input resistance just
    Rid = Rib + R3, where Rib is the resistance looking into the base

    Rib = ie(re + R6/2)/ib
  2. jcsd
  3. Feb 29, 2016 #2
    that is a question indeed !!!...but I think this might not be the forum for this kind of question...try in electrical.stackexchange
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted