Download Winter-06-EE314-Final

EE314 Basic Electrical Engineering II
Winter 2005-06
FINAL EXAM
March 16, 2006
Name:____________________________________
Instructions:
This is a close-book exam and must be completed by you as an individual (ALONE).
You must work all problems and parts. There are thirteen problems on this exam.
The ten problems are multiple choice and will be graded all or nothing. Please circle
your answer for each of these questions. The evaluation of your performance will
take into consideration your understanding expressed in your work, so it is to your
advantage to show as much of the steps you used to solve the problem as possible.
Unclear or illegible work will not receive full credit or partial credit. Use your time
wisely
  Good luck!  
Problem 1 (3%)
Which of the following statements is incorrect?
A. At room temperatures, pure semiconductors make excellent conductors.
B. Doping pure semiconductor material with small amounts of donor impurities produces an n-type
semiconductor.
C. The dominant charge carriers within a doped semiconductor are called majority charge carriers.
D. Conduction within pure semiconductors is termed intrinsic conduction.
Problem 2 (3%)
What is a typical conduction voltage for a silicon diode?
A. 0.25V
B. 0.5V
C. 0.7V
D. 1.1V
Problem 3 (3%)
What would be a typical magnitude for the reverse current in a general-purpose silicon diode?
A. A few picoamps.
B. A few nanoamps.
C. A few microamps.
D. A few milliamps.
Problem 4 (3%)
Assuming that the diode is ideal the values of I and V are:
A.
B.
C.
D.
I = 5mA; V = 5V
I = 2.5mA; V = 2.5V
I = 5A; V = 5V
I = 1.5mA; V = 5V
Problem 5 (3%)
If current exceeds the reverse breakdown voltage of a diode, will current destroy it?
A. Possibly, because current multiplies rapidly in the reverse breakdown region.
B. No, because diode can operate under the reverse bias.
C. Yes, because diode should not operate at breakdown voltage under any circumstances.
D. It does not matter, because diode can operate in reverse or forward bias conditions without
current limit.
Problem 6 (3%)
Which terminal represents the control input of a bipolar transistor?
A. The emitter.
B. The gate.
C. The collector.
D. The base.
Problem 7 (3%)
Which of the following expressions represents the DC current gain of a bipolar transistor?
A. (IC )/(IB+IE)
B. IC /VBE
C. Ic/VBE
D. IC/IB
Problem 8 (3%)
Consider an NMOSFET transistor having Vt0=1V. What is the operation region if: VGS=5V and VDS=10V
A. Saturation
B. Linear
C. Cutoff
Problem 9 (8%)
Determine the ICQ of the following circuit, given that the VBE = 0.7 V,  = 150. Show your work. Circle
only one answer.
A.
B.
C.
D.
2.1 A
2.1 mA
3.15 mA
5.3 mA
Problem 10 (8%)
Determine the output voltage V0 of the following circuit. Show your work. Circle only one answer.
A.
B.
C.
D.
4.3 V
4.8 V
5.5 V
7.1 V
Problem 11 (20%)
Find the range of values for RL so that voltage across it is 15 V. Zener diode parameters are: 15V and 2W.
Answer: __________< RL<_____________
Problem 12 (20%)
Consider the fixed-plus self-bias circuit of figure shown below. Transistor parameters: VDD=12V,
R1=1MΩ, RD=3kΩ, KP=50 A/V2, W = 80m, L = 10 m, and Vt0 = 1V.
Assuming that VDSQ = 6V and IDQ = 1mA determine the values needed for R2 and for RS.
Answer: R2 =_______________ and RS = _______________
Problem 13 (20%)
Determine the gain v0/vi of the circuit shown below.
Rf
R2
1K
100k
R1
R3
100
10k
Vi
5V
V0
R4
10k
Answer: V0/VI =_______________