MCQ in Electronic Circuits Part 8 | ECE Board Exam

(Last Updated On: August 7, 2018)

This is the Multiples Choice Questions Part 8 of the Series in Electronic (Audio/RF) Circuit, Analysis and Design as one of the Electronics Engineering topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electronics Engineering field, Electronics Books, Journals and other Electronics References.

MCQ Topic Outline included in ECE Board Exam Syllabi

• MCQ in Amplifiers
• MCQ in Oscillators
• MCQ in Rectifier
• MCQ in Filters
• MCQ in Voltage Regulation

Continue Practice Exam Test Questions Part 8 of the Series

Choose the letter of the best answer in each questions.

351. Op-amp parameter(s) that is important in large signal dc-amplification.

A. input offset voltage

B. input offset current

C. slew rate

D. all of the above

352. In large signal dc-amplifiers using op-amp, which parameter has the least effect on its performance?

A. drift

B. slew rate

C. input offset voltage

D. input offset current

353. For ac-amplifiers using op-amps what parameters can affect its performance.

A. input offset current and voltage

B. input bias current and voltage

C. drift and slew rate

D. slew rate and frequency response

354. If an op-amp is used to amplify small ac-signals, what parameter you should greatly consider to ensure better performance?

A. input bias current

B. drift

C. frequency response

D. slew rate

355. What do we mean by internally compensated op-amps?

A. Op-amps with internal frequency compensation capacitor to prevent oscillation.

B. Op-amps with an internal compensating resistor to make the output offset voltage zero.

C. Op-amps with internal coupling capacitor to block dc-voltages and allows ac voltages to pass.

D. Op-amps with internal active components to make its gain constant at the entire operating frequency.

356. The frequency at which the open-loop gain of an op-amp is 0.707 times its value at very low frequency

A. threshold frequency

B. break frequency

C. minimum frequency

D. operating frequency

357. What will happen to the voltage gain of op-amp when its operating frequency is increased?

A. also increases

B. increases exponentially

C. will decrease

D. decreases exponentially

358. The reduction of op-amps gain due to increasing operating frequency.

A. Cutoff

B. roll-off

C. diminishing factor

D. reduction step

359. What do we mean by a 20 dB/decade roll-off?

A. a gain reduction by a factor of 10 per decade

B. a gain reduction by a factor of 20 per decade

C. a gain reduction by a factor of 10 per 10 Hz increased in frequency

D. a gain reduction by a factor of 20 per 10 Hz increased in frequency

360. A reduction of op-amp’s voltage gain by a factor of two each time the frequency doubles.

A. 2 dB/octave

B. 2 dB/decade

C. 6 dB/octave

D. 6 dB/decade

361. Frequency at which the voltage gain of op-amp reduces to unity.

A. unity-gain frequency

B. cutoff frequency

C. bandwidth point

D. unity-gain bandwidth product

362. The low and high cutoff frequencies of an amplifier is also called

A. corner frequencies

B. 0.707 frequencies

C. 3-dB frequencies

D. all of these are correct

363. Calculate the cutoff frequency (fc) of an op-amp having a unity-gain bandwidth product B1 = 1 MHz and a open-loop voltage gain AOL = 100,000.

A. 10 Hz

B. 20 Hz

C. 100 Hz

D. 200 Hz

364. An op-amp has a specified transient response rise time of 0.3 µs, calculate its unity-gain bandwidth.

A. 0.857 MHz

B. 1.0 MHz

C. 1.167 MHz

D. 2.334 MHz

365. Rise time is defined as the time required for the output voltage to rise from _______ to ________ of its final value.

A. 0% – 100%

B. 1% – 99%

C. 5% – 95%

D. 10% – 90%

366. The maximum output voltage rate of change of an op-amp.

A. rise time

B. maximum voltage swing

C. differential rate

D. slew rate

367. Factor(s) or parameter(s) that determine(s) the op-amps maximum operating temperature

A. PSRR

B. slew rate

C. unity-gain bandwidth product

D. B and C above

368. What is the maximum signal frequency that can be used in an op-amp having a specified slew rate of 0.5 V/µsec? The maximum output voltage desired is 5 V.

A. 16 kHz

B. 32 kHz

C. 100 kHz

D. 1 MHz

369. What must be the slew rate of an op-amp to be used in order to provide an undistorted output voltage of .10 V ac a frequency of 100,000 rad/sec?

A. 0.1 V/µsec

B. 0.5 V/µsec

C. 1.0 V/µsec

D. 6.28 V/µsec

370. When an op-amp is used as a comparator, the output voltage would be +VSAT if

A. V+ > V-

B. V- > V+

C. V- = V+

D. V- and V+ are both zero

371. Two comparators using op-amps, configured such that it can detect voltage levels within a certain range of values rather than simply comparing whether a voltage is above or below a certain reference.

A. analog comparator

B. regenerative comparator

C. parallel comparator

D. window comparator

372. What gain is significant when an op-amp is used as a voltage comparator?

A. open-loop gain

B. common gain

C. differential closed loop gain

D. closed loop gain

373. An op-amp zero-crossing detector without hysteresis,

A. uses a resistor as its feedback element

B. uses a capacitor as its feedback element

C. uses an inductor as its feedback element

D. has no feedback

374. The feedback element of a differentiator constructed from op-amp is

A. a resistor

B. an inductor

C. a capacitor

D. an RC network

375. An active integrator uses an op-amp, what is its feedback element?

A. Resistor

B. capacitor

C. inductor

D. RC network

376. The voltage gain of an op-amp voltage follower.

A. unity

B. Rf/Ri

C. 1 + Rf/Ri

D. depends on the type of op-amp

377. Calculate the closed-loop voltage gain of an inverting amplifier having a feedback and an input resistance of 100 kΩ and 10 kΩ, respectively.

A. 10

B. 11

C. 100

D. 110

378. The gain of an inverting amplifier is determined by the ratio of the feedback and input resistors (Rf/Ri), meaning we can select any value of resistors as long as its ratio is the same. What op-amp parameter that helps us determine the appropriate values of these resistors?

A. CMRR

B. PSRR

C. SR

D. input bias current

379. What is the noise gain of op-amps?

A. equal to the open loop gain

B. Rf/Ri

C. 1 + Rf/Ri

D. equal to the common gain

380. A unity-gain summing amplifier has three inputs, V1 = 1.0 mV, V2 = 1.5 mV, and V3 = 2.5 mV, calculate the total output voltage.

A. 2.5 mV

B. 3.5 mV

C. 4.0 mV

D. 5.0 mV

381. The random voltage at the output of an op-amp which could occupy the entire bandwidth.

A. noise

B. hash

C. interference

D. all of the above

382. Which of the following of the resistor combinations that provides lesser noise in op-amp circuits?

A. Make both the feedback and input resistances as large as possible

B. Make the feedback as large as possible, while the input as low as possible.

C. Make the feedback as low as possible, while the input as large as possible.

D. Make the feedback and input resistances as small as possible.

383. In most ac-amplifiers using op-amps, the feedback resistor is shunted with a very small capacitance, what is its purpose?

A. to prevent oscillation

B. to improve stability

C. to minimize high frequency noise

D. to compensate for high frequency loss

384. Approximate the noise gain of an inverting adder using op-amps if it has five inputs.

A. unity (1)

B. two (2)

C. four (4)

D. six (6)

385. Op-amps with internal frequency compensation are very stable with respect to signal frequencies. However, the trade-off for frequency stability is (are)

A. limited small-signal bandwidth

B. slow slew rate

C. limited open-loop frequency response

D. all of these

386. What do we mean by externally compensated op-amps?

A. op-amps with frequency-compensation terminals

B. op-amps with provision to externally compensate for frequency stability

C. op-amps whose gain is externally compensated

D. A and B above

387. What is true about the external frequency-compensation capacitor?

A. the higher its value, the wider is its bandwidth

B. the lower its value, the wider is its bandwidth

C. the higher its value, the faster its slew rate

D. A and C above

388. Typical value of the external frequency-compensating capacitor of op-amps.

A. 3 – 30 nF

B. 30 – 300 nF

C. 0.3 – 3.0 µF

D. 3.0 – 30 µF

389. What do we mean by a general-purpose op-amps?

A. op-amps with limited unity-gain bandwidth up to approximately 1 MHz

B. op-amps with slew rate about 0.5 V/µsec

C. op-amps that has unlimited application

D. A and B above

390. Op-amps designed to operate at high slew rate, about 2000 V/µsec and at high frequencies, more than 50 MHz.

A. general purpose op-amps

B. high power op-amps

C. high-stability op-amps

D. high-frequency, high-slew rate op-amps

391. Generally, where does hybrid op-amps found its application?

A. for high-output voltage

B. for high-output current

C. for high-frequency

D. A and B above

392. The magnitude of the op-amps input offset voltage before it can be classified as a low-input offset voltage op-amp

A. 0.2 mV

B. 2.0 mV

C. 2.5 mV

D. 5.0 mV

393. Op-amps whose internal transistor biasing can be controlled externally are categorize as

A. general purpose op-amps

B. programmable op-amps

C. variable op-amps

D. externally compensated op-amps

394. What op-amp parameter(s) that can be governed by the bias control in a programmable op-amp?

A. open-loop gain and slew rate

B. unity-gain bandwidth

C. input bias current

D. all of the above

395. The most popular op-amp packages are the metal can, 8-pin DIP, and the SMT. Which of these corresponds to TO-99?

A. metal can

B. 8-pin DIP

C. SMT

D. all of the above

396. Dual-in-line or DIL package is designated as

A. TO-99

B. TO-91

C. TO-116

D. TO-220

397. For high density ICs involving many op-amps, what packaging is suitable?

A. metal can

B. 14-pin DIL

C. SMT

D. flat-pack

398. Example(s) of surface-mounted technology (SMT) devices.

A. PLCCs

B. SOICs

C. LCCCs

D. all of the above

399. Which condition must exist for a circuit to oscillate?

A. It must have a negative feedback sufficient to cancel the input

B. It must have a gain of less than 1

C. It must have a positive feedback sufficient to overcome losses

D. It must be neutralized

400. Which of the following is not an essential part of an oscillator?

A. Source of energy that supply the losses in tank circuit.

B. A resistor IC combination circuit.

C. Resonant circuit consist of inductance and capacitance.

D. Regenerative feedback circuit.

Questions and Answers in Electronic Circuits

Following is the list of practice exam test questions in this brand new series:

Complete List of MCQ in Electronics Engineering per topic