Question

The transfer characteristics of a base biased common emitter transistor is shown in the figure.

Which of the following statements are true?

• A. At $V_i=1V$, it can be used as an amplifier
• B. At $V_i=0.5V$, it can be used as a switch turned off
• C. At $V_i=2.5V$, it can be used as a switch turned on.
• D. All of these

Answer 1

Answer: (D)

From the given transfer characteristics of a base biased common emitter transistor,
$(i)$ When $V_i=1V$, which is in between $0.6V$ to $2V$, the transistor circuit is in active state and is used as an amplifier.
$(ii)$ When $V_i=0.5V$, there is no collector current. The transistor is in cut off state. The transistor circuit can be used as a switch turned off.
$(iii)$ When $V_i=2.5V$, the collector current becomes maximum and transistor is in saturation state and can be used as switch turned on state.