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

Related Mcqs:

1. 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

2. 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

3. 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

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

   A. Only the temperature
   B. only the β of the transistor
   C. Both Temperature & β
   D. None of the above

5. Three identical amplifiers with each one having a voltage gain of 50,input resistance of 1KΩ & output resistance of 250 ,are cascaded.The open circuit voltage gain of combined amplifier is_________?

   A. 49dB
   B. 51dB
   C. 98dB
   D. 102dB

6. Most of the linear ICs are based on the two-transistor differential amplifier because of its___________?

   A. input voltage dependent linear transfer characteristic
   B. high voltage gain
   C. high input resistance
   D. high CMRR

7. 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

8. 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

9. 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

10. In a common emitter, unbypassed resister provides___________?

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