This module introduces circuit elements such as transistors and FETs and shows how they can be used as amplifiers and switches.The amplification and bias conditions for transistor amplifiers are analysed and discussed in detail.

Circuit elements necessary for building operational amplifiers such as the long tailed pair and the current mirror are analysed, and a complete circuit for an operational amplifier is discussed.

Some applications of operational amplifiers such as the function generator and instrumentation amplifier are introduced with practical applications.

Circuits using MOSFETs for logic and analogue switches are described.