

We will discuss more about this topic in later session. If transistor wants to works as an amplifier we should make the transistor to work in active region which lies between the saturation and cutoff region. Transistor will get completely on at saturation region and completely get off at cutoff region. Here we will concentrate how transistor is used as amplifier. Applications of amplifier are of wide range, they are mainly used in communications, controllers, audio and video instruments etc.

The input signal may be a current signal, voltage signal or a power signal amplifier will amplify the signal without changing its characteristics. Amplification is a process of increasing the signal strength by increasing the amplitude of a given signal with out changing its characteristics.
