February 17, 2004 wlg
ECE 300
Spring Semester, 2004
HW Set #4
Name__________________
Print (last, first)
Use engineering paper. Work only on one side of the paper. Use this sheet as your cover sheet, placed on top of your work and stapled in the top left-hand corner. Number the problems at the top of the page, in the center of the sheet. Do neat work. Underline your answers.
Show how you got your equations . Be sure to show how you got your answers. Each problem counts 5 points.
(1). Find V
0 in the op-am circuit of Figure 1. Ans. V
0
= 2 V
2 k

50 k

1 mA
4 V
+
V
0
_
10 k

0.4 V
I
0
20 k

Figure 1: Circuit for Extra 1. Figure 2: Circuit for Extra 2.
(2) Find I
0
in the op-amp circuit of Figure 2. Ans. I
0
= 120

A
(3) Find I
X
in the op-amp circuit of Figure 3. Ans. V
0
= 6 V, I
X
= -2 mA
1 k

4 k
 I
X
+
_
4 V
2 k

3 k

+
V
O
_
Figure 3: Circuit for Extra-3.

4.10 Superposition: I
O
= 2.4 mA
4.26 Source Transformation: V
O
= - 0.3 V
4.33
Thevenin: V
O
= 4.8 V
4.40 Thevenin: V
O
= 6.86 V
4.xx Thevenin: Find the Thevenin equivalent circuit to the left of A-B in the circuit below and then find I
O
in the output resistor. Ans: V
TH
= 8 V, R
TH
= 4

, I
O
= (1/3) A.
50

20

8


A
50
 +
_ 20 V 1 A
5

12

I
O
Figure 4.xx: Circuit for problem 4.xx.
4.50 Thevenin: V
TH
= 0 V, R
TH
= 1,000

4.62 Norton: I
O
= 2 mA, R
N
= 1.33 k

4.65 Norton: R
N
= 2.12 k

, I
N
= 5 mA, I
O
= 2.57 mA
4.69
Using Thevenin: V
OS
= V
TH
= 24 V, R
TH
= 4 k

, V
AB
= 20 V
4FE-1 Maximum Power Transfer: R
L
= 2 k

for maximum power transfer, P
L,max
= 8 mW