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Showing posts with the label FET

FET Amplifier Configurations

When using FETs as amplifiers, the input signal is applied across two  terminals of the FET and the output is taken across two terminals.

Three FET amplifier configurations:

common source,common gate, andcommon drain.
Common Source Amplifier       The Common Source (CS) amplifier is the FET equivalent of the common  emitter transistor amplifier configuration. Like the CE amplifier, it is capable of high voltage gain. The CS amplifier has the input applied between the gate and source Terminals and the output signal taken across the drain and source terminals. Therefore, the source terminal is common to both the input and output signals. Use of coupling capacitors CIN and COUT. Their function is to block the DC or bias current from entering the AC signal source and load resistor RL.Conversely, during AC operation they couple the AC signal source to the input of the amplifier and the resulting output to the load resistor. Bypass capacitor C1 is used to bypass the source resistor and incre…