The Grounded-Collector Amplifier

Author: N.H. Crowhurst

The remaining possibility for connection of a transistor-grounded collector - is very like the cathode-follower connection of a vacuum tube. In this arrangement, the voltage between base and emitter is small because it is in the direction of easy current flow. The collector-circuit resistor is connected in the emitter circuit, hence the collector-emitter current fluctuations pass through it, causing an output voltage between the emitter and ground. Because the base is used for the input connection, both the a-c and d-c components of the input current are much smaller than in the output current.

Grounded-collector amplifier: A large voltage and small current at the input control almost the same voltage at a much larger current at the output.