MCQ in Solid State Devices Part 11 | ECE Board Exam

This is the Multiples Choice Questions Part 11 of the Series in Solid State Devices/Circuits 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

• MCQs in Semiconductor Fundamentals
• MCQs in Transistor Components
• MCQs in Circuit Analysis and Design
• MCQs in Special Services (Photo Electric, Photo voltaic)

Continue Practice Exam Test Questions Part 11 of the Series

Choose the letter of the best answer in each questions.

501. In dc biasing, it means quiet, still, inactive

A. passive

B. quench

C. static

D. quiescent

502. The transistor terminal that handles most current

A. base

B. collector

C. emitter

D. collector and emitter

503. Which indicates the degree of change, in operating-point due to temperature variation in the dc biasing?

A. temperature coefficient

B. factor of safety

C. merit factor

D. stability factor

504. What best describes the transistor current that flows between the collector and emitter terminals when the base is open?

A. leakage current

B. cut-off current

C. reverse saturation current

D. all of these

505. Solve for the base current if collector current is 600 mA and the current gain is 20.

A. 30 mA

B. 3 mA

C. 12 mA

D. 1.2 mA

506. When the transistor is saturated, VCE is approximately

A. 0 V

B. ½ VCC

C. VCC

D. infinite

507. Collector-emitter resistance of ideal transistor at cut-off

A. 0 Ω

B. infinite

C. a function of the load resistance

D. a function of the collector current

508. The leakage current that flows at the collector-base junction when the emitter is open

A. ICO

B. ICBO

C. ICEO

D. ICBE

509. A transistor with β = 100 is connected as common base, was found to have a leakage current ICBO = 1 µA. If the transistor is configured as common emitter, what is the approximate value of its I_CEO?

A. 0.01 µA

B. 1.0 µA

C. 100 µA

D. 10 mA

510. The most correct technical term of the reverse leakage current that flows between the collector and base junctions when the emitter is open circuited.

A. leakage current

B. saturation current

C. reverse saturation current

D. cut-off current

511. How is the collector cut-off or reverse saturation current ICBO related to the emitter cutoff current IEBO?

A. ICBO ≈ β IEBO p

B. ICBO ≈ IEBO/β

C. ICBO ≈ IEBO(1-α)

D. ICBO ≈ IEBO

512. ICBO of an ideal transistor

A. increases as temperature increases

B. increases as temperature decreases

C. is not affected by a temperature change

D. is zero (0) mA

513. The maximum voltage that can be applied across the collector-emitter terminal for a given transistor is specified as

A. VCEO

B. VECO

C. V(BR)BEO

D. V(BR)CEO

514. If the current-gain-bandwidth product of transistor is 250 MHz and is operated at 100 MHz, what is the effective current gain of the transistor?

A. 2.5

B. 25

C. 250

D. 350

515. The current gain of a transistor decreases as the operating frequency increases. As the operating frequency is increased continuously, a point occurs where the current gain becomes unity. This point, is best described by what transistor parameter?

A. unity gain frequency

B. 0 dB frequency

C. cut-off frequency

D. unity gain bandwidth product or unity current gain bandwidth product

516. When base is common to both the input and output sides of the configuration and is usually the terminal closes to, or at ground potential, it is called what?

A. common-emitter terminology

B. common-collector terminology

C. common-base terminology

D. all of the these

517. Which transistor configuration has the highest input resistance?

A. common base

B. common emitter

C. common collector

D. common transistor

518. One of the following amplifier characteristic refers to that of a common-base (C-B) as compared to common-emitter (C-E) and common-collector (C-C) amplifiers.

A. Has larger current gain

B. Has lower input resistance

C. Has higher input resistance

D. Has larger voltage gain

519. A transistor is said to be configured as common emitter if the emitter terminal is

A. grounded

B. connected to V+

C. floating

D. not used as an input nor output

520. Most frequently used transistor configuration for pnp and npn

A. common-base

B. common-collector

C. common-emitter

D. A and C above

521. Calculate the common-emitter amplification factor β of a transistor with a common-base amplification factor α = 0.99.

A. 10

B. 50

C. 100

D. 200

522. Which transistor configuration hybrid parameters, that is usually specified by the manufacturers?

A. for common-base

B. for common-collector

C. for common-emitter

D. a combination of the three configurations

523. For a common-emitter transistor configuration, the hybrid parameter hfe stands for forward transfer current ratio. This parameter is approximately equal to

A. HFE

B. βac

C. β

D. all of these

524. Hybrid parameter that is usually neglected in circuit analysis

A. hi and ho

B. hr and hf

C. hi and hf

D. hr and ho

525. The input impedance of a common-base configuration is hib, and its magnitude is approximately equal to

A. hie/hfe

B. hie/(1+β)

C. re for dynamic model

D. all of these

526. In most transistor input equivalent circuit it comprises of a resistor and a

A. voltage source

B. stiff voltage source

C. current source

D. stiff current source

527. Which transistor configuration has the highest input resistance?

A. common-base

B. common-collector

C. common-emitter

D. emitter follower

528. Common-base configuration has a high voltage gain and a current gain of

A. low

B. moderate

C. high

D. approximately equal to one (1)

529. Common-collector has the lowest power gain and a voltage gain of approximately one. In contrast to this, what configuration has the highest power gain?

A. common-base

B. common-collector

C. common-emitter

D. emitter follower

530. Which of the following transistor characteristic curves that is most useful?

A. input characteristic curve

B. output characteristic curve

C. transfer characteristic curve

D. all of the above

531. The graph of the product of collector-emitter voltage VCE and collector current IC in the transistor output characteristic curve.

A. maximum power curve

B. minimum power curve

C. saturation power curve

D. breakdown curve

532. The base of a transistor serves a purpose to what element of the FET?

A. source

B. ground

C. substrate

D. gate

533. What is the primary difference between the BJT and the FET?

A. current-controlled device and voltage-controlled device, respectively

B. voltage-controlled device and current-controlled device, respectively

C. impedance transformed device and conductance transformed device, respectively

D. A and C above are correct

534. Another difference between a BJT and a FET with regards to its normal biasing.

A. The input circuit is forward-biased for BJT while reverse for FET.

B. The input circuit is reverse-biased for BJT while forward for FET.

C. The output circuit is forward-biased for BJT while reverse for FET.

D. The output circuit is reverse-biased for BJT while forward for FET.

535. Field-effect transistors (FETs) offer high input impedance than BJT. What makes FETs have high input impedance?

A. The way FETs are constructed.

B. Because of the materials used.

C. Due to the level of doping

D. Due to the reverse-biased input circuit of FETs

536. The operation of BJT involves both the flow of electrons and holes and is therefore, considered as a bipolar device. Unlike BJT, FET’s operation involves only either electrons or holes and is considered as a _________ device.

A. single polar

B. unipolar

C. unpolar

D. polarized

537. Considered as the basic FET or the simplest form of FET

A. JFET

B. MOS-FET

C. IGFET

D. VMOS-FET

538. Junction field effect transistor or JFET has three terminals, which corresponds to the EB-C of the BJT?

A. D-S-G

B. D-G-S

C. S-G-D

D. S-D-G

539. One obvious advantage of a JFET over BJT is its

A. high voltage gain

B. high current gain

C. high input resistance

D. high output resistance

540. A BJT is a current-controlled current-source device while JFET is a ___________ device.

A. current-controlled voltage-source

B. voltage-controlled voltage-source

C. voltage-controlled current-source

D. voltage-controlled transconductance-source

541. What do you call the area in a JFET where current passes as it flows from source (S) to drain (D).

A. channel

B. substrate

C. depletion

D. drift

542. What will happen to the channel of a JFET as current flows to it?

A. widens

B. narrows

C. skews

D. nothing

543. For a normal operation of an n-channel JFET, how do you bias the gate-source junction?

A. positive-negative respectively

B. negative-positive respectively

C. forward-biased

D. any of the above

544. The voltage across the gate-source terminal of a FET that causes drain current ID equal to zero.

A. saturation voltage

B. threshold voltage

C. cut-off voltage

D. pinch-off voltage

545. The current that flows into the channel of a JFET when the gate-source voltage is zero.

A. drain-source saturation current

B. drain-source cut-off current

C. drain-source leakage current

D. drain-source pinch-off current

546. The graph of the drain current ID versus drain-source voltage VDS with VGS as the parameter.

A. transfer characteristic curve

B. output characteristic curve

C. input characteristic curve

D. current-voltage characteristic curve

547. In FET, the conduction path of the output is controlled by the electric field as its name implies. How does an electric field in FET established?

A. By the charges present at the gate due to the reverse-biased junction.

B. By the application of reverse-biased between the gate and drain.

C. By the charges produced due to the applied potential between drain and source VDS.

D. By the charges present at each terminal due to the applied potential.

548. An early version of the field effect transistor in which limited control of current carriers near the surface of a semiconductor bar or film was obtained by an external electric field applied transversely.

A. fieldistor

B. JFET

C. IGFET

D. MOSFET

549. A FET in which the gate electrode consists of a pn junction

A. JFET

B. fieldistor

C. MOS-FET

D. IGFET

550. Which type of FET has the lowest input resistance?

A. JFET

B. MOS-FET

C. IGFET

D. VMOSFET

Questions and Answers in Solid State Devices

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Complete List of MCQ in Electronics Engineering per topic