Q.Write a note on the applications of CB, CC and CE amplifiers.

Because each configuration has a different impedance and gain profile, each is used where those properties are an advantage. …

[!TLDR]

CB amplifiers suit high-frequency work, CC amplifiers suit impedance matching/buffering, and CE amplifiers suit general voltage and power amplification — each application following from its impedance and gain characteristics.

Applications of the three configurations:

1. Common-base (CB) amplifier: it has low input impedance, high output impedance and a good high-frequency response (no Miller effect). It is used as a radio-frequency (RF) amplifier, as the upper transistor in a cascode amplifier, for impedance matching from a low-impedance source to a high-impedance load, and as a pre-amplifier for low-impedance sources such as certain microphones.

2. Common-collector (CC) amplifier / emitter follower: it has high input impedance, low output impedance and a voltage gain near unity. It is used for impedance matching (connecting a high-impedance source to a low-impedance load without loading the source), as a buffer or isolating stage between stages, as the output/driver stage that drives low-impedance loads such as loudspeakers, and as a current amplifier. …