chapter  12
24 Pages

Amplifiers: Basic MOSFET Configurations

The MOSFET will be used here in a network to amplify a signal provided by an input source, which furnishes the input pairs vs and is swinging around the zero value.

These signal pairs (directly or indirectly) fed into the MOSFET will produce in it the voltages and current )(v tgs , )(v tds , )(v tdg , )(i tds which, if no bias is introduced, swing around zero as well. But this results in a problem, because if the MOSFET would “work” in the red circular area, depicted in Figure 12.1, around the origin O of the axes of its output characteristic curves, it does not produce in output the requested amplification of the input signal, but a “distorted” version of it.