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

Confusin on BJT Small-Signal Model (Hybrid-Pi)

  1. Sep 27, 2009 #1
    I'm confused about how exactly the output resistance and other resistances are set up in the small signal model. Is this small signal model correct? Please regard underscores as a subscript. Is r_0 always connected between collector and emitter?

    Attached Files:

  2. jcsd
  3. Sep 28, 2009 #2


    User Avatar
    Science Advisor
    Gold Member

    Hello KingNothing

    Your model doesn't look like what I remember, so I did a little search and found this site that has a similar model for equivalent circuits modified to incorporate Early effect. And yes, the output resistance would be across the collector and emitter.
    http://people.seas.harvard.edu/~jones/es154/lectures/lecture_3/bjt_models/bjt_models.html" [Broken]
    Last edited by a moderator: May 4, 2017
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook