
Switched-Capacitor Building Blocks
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3.6 Signal-Flow-Graph Analysis of Switched-Capacitor Circuits
Signal-Flow-Graph Analysis
As Section 3.3 showed, using charge equations to analyze SC circuits could be
tedious, even for obtaining the transfer function of a simple SC integrator. As a
result, a very useful and simple method called the signal-fl ow-graph (SFG) analysis
based on the principle of superposition has been widely adopted in practice
[9][10][13][19][20][21].
Consider the fi rst-order switched capacitor fi lter shown in Figure 3.11(a). Based
on the principle of superposition, we realize that this circuit can be decomposed into
three acti