Common Gate Amplifier

Common Gate Amplifier

This is an amplifier where the input is applied to the Source and output is collected across the Drain.

The Gate is connected to a dc voltage called bias which ensures the device is operating properly.

The figures 10 (a) and (b) show two different circuits depicting the operation of Common Gate Amplifier / connection

Figure 10 (a) Common Gate with Direct Coupling (b) Common Gate with Capacitive Coupling

In Figure 10(b), the MOS is biased by a constant current source and the signal is capacitively coupled to the input of the circuit