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!

Another transistor problem

  1. Jun 30, 2010 #1
    [PLAIN]http://img256.imageshack.us/img256/2164/transistor.jpg [Broken]

    i should find Re so that transistor works in saturation region

    also i should find Ib in saturation region

    Rc=2kΩ , R1=2kΩ , EB=5V, Vcc=10V, V1=3V, β=100

    im really confused with R1 and V1 i dont know what is their function

    i know that in saturation region Vce = 0

    also from the diagram i can see that

    Eb - 0.7 = Vre so Vre = 4.3 Volts

    Ie = Vre/Re

    if we assume that Ie = Ic

    then

    Ic = Vre/Re

    Ic is Vcc/Rc = 10/2000 = 5mA

    so Re should be Vre/5mA = 4.3/5*10^-3 = 0.86 KΩ

    but does this Re stand for saturation region?
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jul 1, 2010 #2
    Your calculation for Ie doesnt take into account current flowing due to Vcc or V1 in the resistor Re. Use Kirchoff's laws.
     
  4. Jul 1, 2010 #3
    we have

    Eb - 0.7 = Ic1*Re we find Ic1 from Eb

    Vcc - Ic(Rc+Re) - Vce = 0
    V1 - Ic(R1+Re) - Vce = 0

    we find Vce from these two statements and Ic which I will have to add Ic1?

    and how can this help me solve the problem?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Another transistor problem
  1. Transistor problem (Replies: 9)

  2. Transistor problem! (Replies: 1)

Loading...