Electrical Engineering Department
King Fahd University of Petroleum & Minerals
EE 303 Electronic Circuits II
Final Exam
Tuesday, 07th June 2011
07:30 am – 10:00 am
Dr. Badr Abdullah
Name
ID Number
Section Number
Problem
Score
Out of
1
10
2
20
3
20
4
20
Total
Good luck
Problem 1
Identify the filter type of the following transfer functions; then draw each circuit giving all
component values.
=
−10s
+ 10
10
= + 10 + 10
Problem 2
The following circuit has the following properties; supply voltage is ±10V, R1=100kΩ,
R2=R=1MΩ and C=0.01µF. The period is given by = 2 a) Calculate the frequency of oscillation.
b) Sketch , .
c) How would you modify this circuit so that the frequency of oscillation becomes a
function of temperature.
d) Based on the given oscillator circuit, design a new circuit to obtain a triangular and sine
wave outputs.
R1
R2
v+
-VCC
vo
+VCC
R
v−
C
Problem 3
Consider the following amplifier, neglect ro;
a) Identify the amplifier type.
b) Draw the A circuit.
c) Give an expression for A, Af and β.
d) Give an expression for Ri and Ro.
VCC
VCC
RC
I
Vo
CC
RL
Q2
Q1
Io
Rs
Vs
Rf
RE
Problem 4
The amplifier shown below has Rsig=RL=1kΩ, RC=1kΩ, RB=47kΩ, β=100, Cµ =0.8pF,
rπ=4.63kΩ, gm=21.6mA/V and fT=600MHz.
a) Neglecting ro and rx, calculate the midband gain .
b) Calculate fH.
c) If RB is now connected between the base and collector of the BJT, calculate the
component of Rin that arises as a result of RB.
d) Re-calculate fH.
VCC
RC
CC
Vo
RL
Rsig
Vsig