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Amplifier Model

Enough of filters. Lets now look at the simple amplifier model in figure 3.14

Figure 3.14:  A simple amplifier model.

Notice that is with respect to ground while is a voltage difference. For a typical operational amplifier at . As , due to internal capacitance, ie. the amplifier behaves like a low-pass filter.

where is the transfer function of a low-pass filter.

Doug Gingrich
Tue Jul 13 16:55:15 EDT 1999