Introducing a resistor in the emitter of a common amplifier stabilizes the dc operating point against variations in____________?

Related Mcqs:

1. An amplifier using an opamp with slew rate SR=1v/µsec has a gain of 40db.if this amplifier has to faithfully amplify sinusoidal signals from dc to 20 KHz without introducing any slew-rate induced distortion, then the input signal level must not exceed________?

   A. 795mV
   B. 395mV
   C. 795 mV
   D. 39.5mV

2. An amplifier without feedback has a voltage gain of 50,input resistance os 1 KΩ & Output resistance of 2.5KΩ.The input resistance of the current-shunt negative feedback amplifier using the above amplifier with a feedback factor of 0.2 is___________?

   A. 1/11KΩ
   B. 1/5KΩ
   C. 5KΩ
   D. 11KΩ

3. A change in the value of the emitter resistance Re in a differential amplifier?

   A. affects the difference mode gain Ad
   B. affects the common mode gain Ac
   C.affects both Ad and Ac
   D. does not effect either Ad and Ac

4. In the differential voltage gain & the common mode voltage gain of a differential amplifier are 48db &2db respectively, then its common mode rejection ratio is__________?

   A. 23dB
   B. 25dB
   C. 46dB
   D. 50dB

5. When a transistor is connected in common emitter mode, it with have__________?

   A. negligible input resistance and high output resistance
   B. high input resistance and low output resistance
   C. medium input resistance and high output resistance
   D. low input resistance as well as output resistance

6. In a common emitter, unbypassed resister provides___________?

   A. voltage shunt feedback
   B. current series feedback
   C. negative voltage feedback
   D. positive current feedback

7. A differential amplifier has a differential gain of 20,000 . CMRR=80 dB. The common mode gain is given by________?

   A. 2
   B. 1
   C. 1/2
   D. 0

8. A differential amplifier is invariably used in the i/p stage of all OP-amps. This is done basically to provide the OP-amps with a very high_________?

   A. CMMR
   B. Bandwidth
   C. Slew rate
   D. Open-loop gain

9. The most commonly used amplifier in sample & hold circuits is______________?

   A. A unity gain non-inverting amplifier
   B. A unity gain inverting amplifier
   C. An inverting amplifier with a gain of 10
   D. An inverting amplifiers with a gain of 100

10. In a CB amplifier the maximum efficiency could be____________?

    A. 99%
    B. 85%
    C. 50%
    D. 25%