18-04-2014, 03:26 PM
COMMON SOURCE FET AMPLIFIER
AIM:
1. To obtain the frequency response of the common source FET
Amplifier
2. To find the Bandwidth.
APPRATUS:
N-channel FET (BFW11)
Resistors (6.8KΩ, 1MΩ, 1.5KΩ)
Capacitors (0.1µF, 47µF)
Regulated power Supply (0-30V)
Function generator
CRO
CRO probes
Bread board
Connecting wires
THEORY:
A field-effect transistor (FET) is a type of transistor commonly used for weak-signal amplification (for example, for amplifying wireless (signals). The device can amplify analog or digital signals. It can also switch DC or function as an oscillator. In the FET, current flows along a semiconductor path called the channel. At one end of the channel, there is an electrode called the source. At the other end of the channel, there is an electrode called the drain. The physical diameter of the channel is fixed, but its effective electrical diameter can be varied by the application of a voltage to a control electrode called the gate. Field-effect transistors exist in two major classifications. These are known as the junction FET (JFET) and the metal-oxide- semiconductor FET (MOSFET). The junction FET has a channel consisting of N-type semiconductor (N-channel) or P-type semiconductor (P-channel) material; the gate is made of the opposite semiconductor type.
RESULT:
The frequency response of the common source FET
Amplifier and Bandwidth is obtained.