I.
Operational Amplifiers
These devices were first a basic building block in analog computers. They were called
operational because they were used to implement mathematical operations. Now they are used
more broadly but the name remains.
In an op-amp, the
Node-Voltage or Nodal Analysis
Our next set of techniques commonly used in circuit analysis are Nodal and Loop Analysis.
Both of these techniques give you a systematic way of solving a problem. In nodal analysis, the
following 4 steps should be followed.
I. Loop-current (mesh) Analysis
This technique is similar to nodal analysis. This time, the objective is to find loop currents (rather
than node voltages) and you will use KVL (rather than KCL) and Ohms Law to solve for loop
currents. The steps are:
1) La
ECE 121
Homework #1
1. (A) Find the current I and the power absorbed by the resistor:
I
+
12 V
40 k
(B) Find the voltage across the current source and the power supplied by the source:
+
Vs
0.6 mA
6 k
2. In the network below, if Vad is 3V, nd VS .
VS
b
a