1. ECE 1270: Introduction to Electric Circuits
Lecture 12:
Superposition
Chapter 4
Techniques of Circuit Analysis: Sections 4.13

2. Superposition Purpose
Simplify complex circuit with many independent sources.
If a circuit has two or more independent sources, one way to determine the contribution of each independent source to the variable and then add them up.
Steps:
1) Turn off (replace voltage source with short and current source with open) all independent sources except one source. Find the output (voltage or current) due to that active source.
2) Repeat step 1 for each of the other independent sources.
3) Find the total contribution by adding algebraically all the
contributions due to the independent sources.

3. Fig. 4.8 (p.132 Sadiku 4th edition)
Find vo using superposition
Verify it in Multisim

4. Fig. 4.62 a) Find the branch currents using superposition
Students do this problem.
Students verify it in Multisim

5. P4.98
Find i using superposition

6. Example 4.4 (p.132 Sadiku 4th edition)
Find io using superposition (simulation only)
No need to calculate.
Have students verify the value in Multisim