Operational Amplifier and Its Applications MCQs

169. An op-amp has an open-loop gain of 105 and an open-loop upper cutoff frequency of 10 Hz. If this op-amp is connected as an amplifier with a closed-loop gain of 100, then the new upper cutoff frequency is

170. An op-amp, having a slew rato of 62.8 V/msec, is connected in a voltage follower configuration. If the maximum amplitude of the input sinusoid is 10 V, then the minimum frequency at which the slew rate limited distortion would set in at the output is

A. 1.0 MHz

171. The output off-set voltage is zero for the circuit given in the figure 6.11 when

A. VI= 0, 1/3_ =and VI = V2

B. VI = 0 and 1B_ = 1B

C. 113_ =18, and V1= V2

D. VI = 0 and V1= V2

Discussion

172. In a differential amplifier, CMRR can be improved by using an increased

A. emitter resistance

B. collector resistances

C. power supply voltages

D. source resistances

Discussion

173. Consider the following statements :I. A differential amplifier is used at the input stage of an operational amplifier Differential amplifiers have very high CMRIt. Of these statements

A. both I and II are ture and 11 is the correct explanation of I

B. both I and II are true but II is not the ONLY explanation of!

C. I is true but 11 is false

D. I is false but Ills true.

Discussion

174. Ability of an Op. Amp to provide sufficient differential mode signal but to reject the common mode signal is given bY

175. CMRR of a differential amplifier is increased by replacing its emitter resistance by

A. constant voltage source

B. constant current source

C. physically open circuit

D. none of the above

Discussion

Electronics Engineering Objective Questions { Operational Amplifier and Its Applications }