A bipolar junction transistor used in common collector configuration h...
A bipolar junction transistor in cc configuration has high input impedance and low output impedance.
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A bipolar junction transistor used in common collector configuration h...
Introduction:
The common collector configuration, also known as the emitter follower configuration, is one of the three basic configurations of a bipolar junction transistor (BJT). In this configuration, the emitter terminal is common to both the input and output sides of the transistor. The input is applied to the base terminal, and the output is taken from the emitter terminal.
Input Impedance:
Input impedance refers to the impedance seen by the input signal source when connected to the input of a circuit. In the common collector configuration, the input impedance is high. This is because the base terminal is directly connected to the input signal source through a biasing resistor, and the emitter terminal is grounded. As a result, the input signal source sees a high impedance due to the biasing resistor, which provides isolation between the input and the transistor.
Output Impedance:
Output impedance refers to the impedance seen by the load when connected to the output of a circuit. In the common collector configuration, the output impedance is low. This is because the emitter terminal is directly connected to the load resistor, and the collector terminal is connected to the power supply. As a result, the load resistance is directly connected to the low impedance emitter terminal, providing a low output impedance.
Explanation of Option B:
Option B states that the common collector configuration has a high input impedance and low output impedance, which is the correct answer.
- The high input impedance is due to the presence of the biasing resistor between the base terminal and the input signal source. This resistor isolates the input signal source and provides high impedance.
- The low output impedance is due to the direct connection between the load resistor and the low impedance emitter terminal. This direct connection allows for a low output impedance.
Conclusion:
In summary, the common collector configuration of a bipolar junction transistor has a high input impedance and low output impedance. This configuration provides isolation and high impedance at the input side, allowing for efficient coupling with the input signal source. At the same time, it provides a low output impedance, allowing for effective transfer of the amplified signal to the load.