Question

what is the main characteristic of the active region of a bjt? the transistor is off the base - emitter junction is forward biased, and the base - collector junction is reverse biased the transistor is on both the base - emitter and base - collector junctions are reverse biased what is the main use of the common collector amplifier? signal modulation voltage amplification impedance matching current amplification

Explanation:

1. In the active - region of a BJT, the base - emitter junction is forward biased and the base - collector junction is reverse biased. This allows the transistor to function as an amplifier. When the transistor is off, both junctions are reverse biased or there is no proper biasing. When it is on in a non - active sense (saturation), both junctions are forward biased.
2. The common - collector amplifier (also known as an emitter - follower) is mainly used for impedance matching. It has a voltage gain close to 1, so it is not used for voltage amplification. It is not primarily for signal modulation or current amplification.

Answer:

1. The base - emitter junction is forward biased, and the base - collector junction is reverse biased
2. Impedance matching