Please help finding resistance !

ArFa

Dec 7, 2010
17
Joined
Dec 7, 2010
Messages
17
Please can you tell me how to find these parameters: R1=? ; R2=? ; Re=?
if Vcc=18V; Rc=2k(ohm) ; IcQ=4.8 [mA] ; VceQ=6 [V].

the circuit is:
Code:
http://img18.imageshack.us/i/electrocircuit.png/
electrocircuit.png


p.s. Please do it as fast as you can because I'va an exam in Suterday...
 
Last edited by a moderator:

Laplace

Apr 4, 2010
1,252
Joined
Apr 4, 2010
Messages
1,252
What are the standard assumptions you make about the transistor such as Vbe, the current gain, is the current gain high enough to ignore the base current? Then start with the voltage across Rc, given the collector current. Vce is given, so the voltage across Re is simple to find. Knowing the emitter current and emitter voltage gives the value of Re and the base voltage as Ve+Vbe. Knowing the base voltage, calculate R1 & R2 necessary to provide that base voltage.
 
Top