MCQ in Solid State Devices Part 4 | ECE Board Exam

(Last Updated On: July 27, 2018)

This is the Multiples Choice Questions Part 4 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 4 of the Series

Choose the letter of the best answer in each questions.

151. Photoconductive effect means

A. The decreased conductivity of an illuminated semiconductor junction

B. The increased conductivity of an illuminated semiconductor junction

C. The conversion of photonic energy to electromagnetic energy

D. The conversion of an electromagnetic energy to photonic energy

152. What happens to the photoconductive material when light strikes on it?

A. The conductivity of the material decreases

B. Nothing important happens

C. The conductivity of the material stays the same

D. The conductivity of the material increases

153. What type of diode is used for tuning receivers; operate with reverse bias and derived its name from voltage-variable capacitor?

A. Zener diode

B. Tunnel diode

C. Varactor diode

D. Crystal diode

154. What semiconductor material is used in the construction of LED?

A. Silicon

B. Germanium

C. Gallium

D. Gallium arsenide

155. What is approximately the sum of the number of protons and neutrons of an atom?

A. Atomic mass

B. Atomic number

C. Atom subscript

D. Valence shell

156. What is the number of protons in the nucleus or the number of electrons in an atom?

A. Atomic mass

B. Atomic weight

C. Atomic number

D. Free electrons

157. The charge of proton has the same value to that of an electron but

A. Opposite in sign

B. Greater in some cases

C. Lesser than in some cases

D. Usually not important

158. Mass of proton or neutron is __________ times that of an electron.

A. 1386

B. 2000

C. 1836

D. 10

159. A photodiode which conducts current only when forward biased and is exposed to light.

A. LAD

B. LED

C. PIN

D. Photoconductor

160. What is the most commonly used color of an LED?

A. Orange

B. Blue

C. Red

D. Green

161. If the temperature of a semiconductor material increases, the number of free electrons

A. Decreases

B. Increases

C. Remains the same

D. Becomes zero

162. Varactor diode’s transition capacitance is directly proportional to the product of the permittivity of the semiconductor material and PN junction area but inversely proportional to its

A. Resistance

B. Voltage

C. Depletion width

D. Threshold voltage

163. A __________ is a light-sensitive device whose number of free electrons generated is proportional to the intensity of the incident light.

A. Varicap

B. Photodiode

C. Schottky diode

D. LED

164. Which of the following is NOT one of the three distinct regions in the characteristic curve of a diode?

A. Forward bias region

B. Reverse bias region

C. Breakdown region

D. Saturation region

165. Another name for saturation current in a diode, which arises from the fact that it is directly proportional to the cross-sectional are of the diode.

A. Steady-state current

B. Constant current

C. Thermal current

D. Scale current

166. How much voltage would you measure across the base-emitter junction of a silicon transistor at class A?

A. 0 V

B. 0.3 V

C. 3.6 V

D. 0.7 V

167. In an amplifier, the emitter junction is

A. Forward biased

B. Reverse biased

C. Grounded

D. Shorted

168. A manufacturer quotes in his specifications that a germanium diode conducts 50 mA at 1 volt. Determine the bulk resistance.

A. 100 ohms

B. 60 ohms

C. 14 ohms

D. 20 ohms

169. A silicon diode has a maximum allowable junction temperature of 150ºC. Find the maximum allowable power dissipation at 25ºC temperature if the diodes thermal resistance is 0.4 ºC/mW.

A. 238 mW

B. 313 mW

C. 600 mW

D. 117 mW

170. What is the principal characteristic of a zener diode?

A. A constant current under conditions of varying voltage

B. A high forward current rating

C. A constant voltage under conditions of carrying current

D. A very high PIV

171. What device whose internal capacitance varies with the applied voltage?

A. Zener diode

B. Photodiode

C. Tunnel diode

D. Varactor diode

172. The ________ transistor configuration has the highest value of input resistance.

A. Common base

B. Common emitter

C. Emitter-stabilized

D. Common collector

173. A method of connecting amplifiers in cascade

A. Configuration

B. Coupling

C. Link

D. Stages

174. What is the largest region of a bipolar transistor?

A. Base

B. Emitter

C. Collector

D. P-region

175. A diode that has a negative resistance region and widely used in the design of oscillators, switching networks and pulse generators.

A. Hot-carrier diode

B. Tunnel diode

C. LED

D. Schottky diode

176. Refers to a three-layer diode.

A. Shockley diode

B. Schottky diode

C. Diac

D. Triac

177. Diode that operates in the reverse breakdown voltage and is used as a voltage regulator.

A. Varactor diode

B. PIN diode

C. Tunnel diode

D. Zener diode

178. Another name for metal-oxide semiconductor field effect transistor is

A. JFET

B. GFET

C. IGFET

D. Transistor

179. In enhancement-type MOSFETs, the __________ region is used if the FET is to operate as an amplifier.

A. Triode region

B. Diode region

C. Cut-off region

D. Saturation region

180. In enhancement-type MOSFETs, the __________ regions are used for operation as a switch.

A. Triode and saturation

B. Cut-off and saturation

C. Saturation and active

D. Cut-off and triode

181. Unijunction transistor has three terminals, namely

A. Gate, cathode and anode

B. Grid, plate and cathode

C. Base 1, base 2 and emitter

D. Gate, base 1 and base 2

182. What two elements widely used in semiconductor devices exhibit both metallic and nonmetallic characteristics?

A. Gold and silicon

B. Germanium and gold

C. Bismuth and galena

D. Silicon and germanium

183. What happens to the voltage drop across the diode when current flow increases rapidly in a forward-biased diode?

A. Increases

B. Decreases

C. Becomes zero instantly

D. Remains relatively constant

184. What are the majority current carriers in the N-type silicon?

A. Free electrons

B. Holes

C. Bounded electrons

D. Protons

185. What diode gives off light when energized?

A. Photodiode

B. LED

C. Photoconductive cell

D. Tunnel diode

186. What are the solid state gallium arsenide devices that emit beam of radiant flux when forward biased?

A. LEDs

B. Photoconductive cells

C. IR emitters

D. Photodiodes

187. A graphical representation in transistor wherein the emitter current is plotted against the variable emitter base voltage VEB for constant value of collector-base voltage VCB.

A. Static curve

B. Input characteristic curve

C. Output characteristic curve

D. Semilog curve

188. When the collector current Ic is plotted against the collector base voltage at constant emitter Ie, the curve obtain is called

A. Output characteristic curve

B. Linear curve

C. V-I curve

D. Semilog curve

189. Eg for silicon is 1.12 eV and germanium is 0.72 eV. It can be concluded that

A. Less number of electron hole pairs will be generated in silicon than in germanium at room temperature

B. More number of electrons and hole pairs will be generated in silicon than in germanium at room temperature

C. High energy of charges is a property of silicon

D. The relationship of the two is not significant

190. Junction diodes are commonly rated by its

A. Maximum current and PIV

B. Inductance and PIV

C. Capacitance and maximum reverse current

D. Circuits resistance and maximum forward current

191. A special type of diode which is often used in RF switches, attenuators and various types of phase shifting devices is called

A. Zener diode

B. PIN diode

C. Tunnel diode

D. Varactor diode

192. A volt-ampere characteristic curve that describes the relationship of the output voltage of a transistor to its output current is a set input current.

A. Input characteristic

B. Output characteristic

C. Load line

D. Saturation curve

193. The use of __________ coupling is particularly desirable in low level, low noise audio amplifier stages to minimize hum pick up from stray magnetic fields.

A. Transformer

B. Direct

C. RC

D. LC

194. The way in which the gain of an amplifier varies with the frequency is called

A. Logarithmic response

B. Frequency response

C. Voltage response

D. Phase response

195. The maximum rectification efficiency of a half wave rectifier is

A. 81.2 %

B. 40.6 %

C. 20.6 %

D. 25 %

196. The maximum rectification efficiency of a full-wave rectifier is

A. 40.6 %

B. 81.2 %

C. 110 %

D. 92 %

197. A coupled amplifier which has the major advantage of permitting power to be transported from the relatively high output impedance of the first stage to the relative low input impedance of the second stage.

A. RC coupling

B. Transformer coupling

C. Direct coupling

D. Stabilized coupling

198. Electron mobility property of silicon at 300 K is approximately equal to __________ m^2/V-s

A. 1.1

B. 0.135

C. 0.048

D. 45

199. In a push-pull power amplifier, an input transformer can be used as a __________ providing equal amplitude input signals opposite in polarity

A. Phase reversal

B. Phase-splitter

C. Limiter

D. Discriminator

200. If the line frequency is 60 Hz, the output frequency of a bridge rectifier is

A. 30 Hz

B. 60 Hz

C. 120 Hz

D. 240 Hz

Questions and Answers in Solid State Devices

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Complete List of MCQ in Electronics Engineering per topic