Electric Circuits
ECSE 2010
Prof. Shayla Sawyer
HW03
Spring 2015
1) Mesh/Nodal Analysis with Dependent Sources
R2
2k
R4
4k
V1
2V
+
Vx
R1
R6
2k
4k
R5
1k
I1
2E-3 Vx
-
R3
2k
0
In the above circuit:
a) Determine the current produced by I1. (check i3 is 0.154 mA)
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Electric Circuits
ECSE 2010
Prof. Shayla Sawyer
HW03
Spring 2015
2) Thevenin/Norton Equivalent Circuits
V1
4
R2
2k R4
R6
1k
A
3k
I1
2E-3
R3
1.5k
R5
3k
0
RLoad
4k
B
a) Find the voltage between A and B if Rload has a resistance of 4kΩ. (Use PSpice to check!)
b) Replace RLoad with an open circuit and find the voltage between A and B (VThevenin).
c) Replace RLoad with a short circuit and find current from A to B (INorton).
d) Short any voltage sources and open any current sources. Find the resistance between A and B when 'looking'
to the left of the dahsed line (RThevenin). (RLoad is not part of the circuit).
e) Draw the Thevenin circuit with VT, RT and RLoad.
f) In this two resistor circuit, verify that when RLoad is 4kΩ, the voltage between and B is the same as
calculated in a).
g) Draw the Norton circuit, with INorton, RThevenin, and RLoad.
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Electric Circuits
ECSE 2010
Prof. Shayla Sawyer
HW03
Spring 2015
3. Thevenin/Norton Equivalent Circuits - Dependent Sources
V2
R1
4k
3E-3Vx
4Vx
R2
2k
I1
R4
6k
8
V1
RLoad
R5
6k
+
Vx
-
R3
12k
0
Source Circuit
Load Circuit
a) Find VThevenin uisng the Open Circuit method
b) Find INorton using the Short Circuit method
c) Find RThevenin using the test/voltage current method
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Electric Circuits
ECSE 2010
Prof. Shayla Sawyer
HW03
Spring 2015
4. Amplifier Circuits
U4
V1=5V
+
R1
U2
OUT
-
6
R6
+
1k
OPAMP
-
V1
OPAMP
R8
0
0
OUT
-
Vout
OPAMP
1k
U1
R5
0
OUT
-
10k
0
R7
+
V2=8V
+
4k
2k
R2
1k
R4
U3
OUT
OPAMP
2k
R3
5k
a) For the above circuit, determine the output voltage, Vout. The voltages supplied to the op-amps are 9V
and -9V, as appropriate.
5. Amplifier Circuits: Design
a) Design a two stage amplifier such that the output of the first stage is V1 = -4Vin and the output of the
second stage is Vout = -2V1
b) Design an amplifier circuit with three inputs (V1, V2, and V3) such that
Vout = V1 - 2V2 - 4V3
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