Applications of Transistor Biasing
|
Type |
Parameter Analysis |
Application |
|---|---|---|
|
Fixed Bias Circuit |
β dependent, unstable Q point |
Digital Switch |
|
Collector To Base Bias |
Greater stability |
Amplifier |
|
Voltage Divider Bias Circuit |
β independent, stable Q point |
Amplifier |
|
Emitter Bias Circuit |
Greater stability |
Ic driver amplifier |
Transistor Biasing
The transistor was invented in 1948 by John Bardeen, Walter Brattain, and William Shockley at Bell Laboratory in America. The invention of the transistor completely revolutionized the electronic industry. Since then, there has been a rapidly expanding effort to utilize and develop many types of semiconductor devices such as FET, MOSFET, UTJ, SCR, etc. transistors have replaced bulky vacuum tubes in performing many jobs.
When a third doped element is added to the crystal diode in such a way that two P-N junctions are formed, the resulting device is known as a transistor. The transistor━ an entirely new type of electronic device is capable of achieving amplification of weak signals. As the transistor has two P-N junctions, one junction is forward biased and the other junction is reversed biased. The forward-biased junction has a low resistance path whereas a reverse-biased junction has a high resistance path. The weak signal is introduced in the low-resistance, circuit, and output is taken from the high-resistance circuit.
Transistors can operate in three regions namely cut-off, active, and saturation regions. To operate the transistor in the desired region we have to apply the external DC voltages of correct polarity and magnitude to the two junctions of the transistor.
Table of Content
- Transistor Biasing
- Stabilization
- Types
- Collector Biased Circuit
- Solved Example
- Biasing in Amplifier Circuits
- Applications