Expt 3 - Study of OPAMP amplifiers

When a differential amplifier is operated single-ended,

• The output is grounded

• One input is grounded and signal is applied to the other

• Both inputs are connected together

• The output is not inverted

The common-mode gain is ………..

• Very high

• Very low

• Always unity

• Unpredictable

The output of a particular Op-amp increases 8V in 12μs. The slew rate is

• 90 V/μs

• 0.67 V/μs

• 1.5 V/μs

• None of the above

The input offset current equals the

• Difference between two base currents

• Average of two base current

• Collector current divided by current gain

• None of these

If A_DM = 3500 and A_CM = 0.35, the CMRR is

• 1225

• 10000

• 80 dB

• Option 2 & 3

The Op-amp can amplify

• A.C. signals only

• D.C. signals only

• Both A.C. and D.C. signals

• Neither D.C. nor A.C. signals

A certain non-inverting amplifier has Ri of 1 kΩ and Rf of 100 kΩ. The closed-loop voltage gain is ………

• 100,000

• 1000

• 101

• 100

Op-Amp has _______ gain

• High

• Low

• Zero

• Medium

Which of the following electrical characteristics is not exhibited by an ideal op-amp

• Infinite voltage gain

• Infinite bandwidth

• Infinite output resistance

• Infinite slew rate

In a typical op-amp, which stage is supposed to be a dual-input unbalanced output or single-ended output differential amplifier

• Input stage

• Intermediate stage

• Level shifting stage

• Output stage