CHAPTER-1 INTRODUCTION1: A formula is a rule that relates qualities.      a. True      b. FalseThe correct answer is b2: A law summarizes a relationship that already exists in nature.      a. True      b. FalseThe correct answer is a3: A derivation is a formula produced with the use of mathematics.      a. True      b. FalseThe correct answer is a4: In order to avoid loading error, a bipolar junction transistor (BJT) input or analog volt-ohm-milli-ammeter (VOM) is generally used to measure a voltage.      a. True      b. FalseThe correct answer is b5: Norton current is sometimes called the short-circuit current.      a. True      b. FalseThe correct answer is a6: A Thevenin circuit can be converted to a Norton circuit.      a. True      b. FalseThe correct answer is a7: Coulomb?s law states that the force of attraction or repulsion between two charges is inversely proportional to the charges and directly proportional to the square of the distance between them.      a. True      b. FalseThe correct answer is b8: A derivation is a formula that we cannot get from other formulas.      a. True      b. FalseThe correct answer is b9: The second approximation of a dc voltage source does not include internal resistance.      a. True      b. FalseThe correct answer is b10: A dc current source produces a constant load_____for different load resistances.The correct answer is current11: A_____is a circuit often built with solderless connections without regard to the final location of parts.The correct answer is breadboard

12: Source resistance can be ignored when it is at least_____times smaller than the load resistance.The correct answer is 10013: Using the second approximation for an ac voltage source is valid only at_____frequencies.The correct answer is low14: A_____current source has a source resistance that is at least 100 times larger than the load resistance.The correct answer is stiff15: If you calculate a Thevenin resistance of 10 k?, you know that the Norton resistance equals_____.The correct answer is 10 k?16: A poor solder connection referred to as a cold-solder joint usually means_____connection.The correct answer is no17: A type of circuit trouble that appears and then disappears is known as a(n)_____trouble.The correct answer is intermittent18: The ideal approximation is sometimes called:      a. first approximation      b. second approximation      c. third approximation      d. fourth approximationThe correct answer is a19: The term stiff voltage source refers to a voltage source with a load resistance which is      a. 10 times larger than the source resistance      b. 100 times larger than the source resistance      c. equal to the source resistance      d. 100 times smaller than the source resistanceThe correct answer is b20: The most common circuit troubles are      a. faulty power supplies      b. improper design      c. broken switches      d. open and shortsThe correct answer is d21: In a circuit, voltages are usually measured with respect to      a. the positive side of the power source      b. the component known as the fuse      c. ground      d. the loadThe correct answer is c22: In the troubleshooting procedure, after a component has been isolated as the top suspect,      a. replace it right away      b. unsolder or disconnect it and use test equipment for confirmation      c. replace component with a two inch piece of number 16 gauge wire      d. test component in the circuit using an ohmmeterThe correct answer is b23: Thevenin voltage is defined as the voltage across the load terminals when      a. the voltage source is removed

      b. the load resistor is open      c. the load resistor is shorted      d. the voltage source is shortedThe correct answer is b24: Thevenin theorem simplifies calculations and      a. enables us to explain circuit operation      b. troubleshoots transistor circuits      c. serves as a constant current source      d. serves as a constant voltage sourceThe correct answer is a25: When measuring a voltage, what causes a small current to flow through the multimeter?      a. a small load resistance      b. the D?Arsenval meter movement      c. the input impedance      d. the output impedanceThe correct answer is cCHAPTER-2 SEMICONDUCTORS1: Copper is a good conductor.      a. True      b. FalseThe correct answer is a2: The valence orbit controls the physical properties of the atom.      a. True      b. FalseThe correct answer is b3: The core of an atom consists of all inner orbits.      a. True      b. FalseThe correct answer is a4: A semiconductor is an element with electrical properties identical to those of a conductor.      a. True      b. FalseThe correct answer is b5: At room temperature, a silicon crystal acts like a conductor.      a. True      b. FalseThe correct answer is b6: Intrinsic semiconductor has an equal number of free electrons and holes.      a. True      b. FalseThe correct answer is a7: Each pair of positive and negative ions at the pn junction is called a doped pole.      a. True      b. FalseThe correct answer is b8: Forward bias is achieved when the negative source terminal is connected to the n-type material,

and the positive terminal is connected to the p-type material.      a. True      b. FalseThe correct answer is a9: The departure of an electron creates a vacancy in the valence orbit, it is called a_____.The correct answer is hole10: _____is the merging of a free electron and a hole.The correct answer is Recombination11: A(n)_____semiconductor is a pure semiconductor.The correct answer is intrinsic12: Silicon that has been doped with a trivalent impurity is called a_____semiconductor.The correct answer is p-type13: The border between p-type and n-type crystal is called the pn_____.The correct answer is junction14: Junction_____is another name for pn crystal.The correct answer is diode15: In a light-emitting diode (LED), the applied_____lifts the electrons to higher energy levels.The correct answer is voltage16: When a diode is first formed, the_____layer does not exist.The correct answer is depletion17: How many valence electrons are there in a germanium semiconductor?      a. 1      b. 2      c. 4      d. NoneThe correct answer is c18: The term used to describe the sharing of valence electrons that gives a crystal solidity is      a. covalent bonding      b. negative ion      c. saturation point      d. reverse biasThe correct answer is a19: What type of atoms are added to molten silicon in order to increase the number of free electrons?      a. pentavalent      b. trivalent      c. covalent      d. positiveThe correct answer is a20: What is the most popular and useful semiconductor material?      a. silver      b. copper      c. aluminum      d. siliconThe correct answer is d21: When reverse bias is increased

      a. forward current increases      b. depletion layer widens      c. depletion layer becomes smaller      d. the diode becomes polarizedThe correct answer is b22: What is the term for the temperature inside a diode, right at the pn junction?      a. ambient temperature      b. diode temperature      c. pn temperature      d. junction temperatureThe correct answer is d23: When the reverse voltage increases, holes and electrons      a. recombine      b. move away from the junction      c. move toward the junction      d. remain stationaryThe correct answer is b24: What is the term for reverse current on the surface of a crystal?      a. crystal current      b. reverse current      c. surface-leakage current      d. avalanche breakdown currentThe correct answer is c

CHAPTER-3 DIODE THEORY

1: An ordinary resistor is a nonlinear device because the graph of its current versus voltage is a curved line.      a. True      b. FalseThe correct answer is b2: An ideal diode acts like a switch that closes when reverse-biased and opens when forward-biased.      a. True      b. FalseThe correct answer is b3: You can quickly check the condition of a diode with a voltmeter on a high voltage range.      a. True      b. FalseThe correct answer is b4: A diode that measures extremely low resistance in both directions is called a shorted diode.      a. True      b. FalseThe correct answer is a5: Much of the information on a manufacturer?s data sheet is very important and of use to

technicians and circuit designers.      a. True      b. FalseThe correct answer is b6: Manufacturer?s data sheets generally do not list the value of bulk resistance.      a. True      b. FalseThe correct answer is a7: The ratio of total voltage to total diode current is the bulk resistance of the diode.      a. True      b. FalseThe correct answer is b8: The load line is a tool used to find the exact value of a diode?s dc resistance.      a. True      b. FalseThe correct answer is b9: Surface mount diodes are small and efficient.      a. True      b. FalseThe correct answer is a10: The p side of a diode is referred to as the_____.The correct answer is anode11: The sum of the ohmic resistance is called the_____resistance.The correct answer is bulk12: All silicon diodes have a knee voltage of approximately_____volts.The correct answer is 0.713: A diode can be effectively checked by using a(n)_____.The correct answer is ohmmeter14: A diode that exhibits high resistance in both directions when measured with an ohmmeter is_____.The correct answer is open15: The knee voltage of a germanium diode is approximately_____volts.The correct answer is 0.316: The ratio of total diode voltage to total diode current is the_____resistance.The correct answer is dc17: When graphing diode characteristics, a tool used to find the exact value of diode current and voltage is the_____line.The correct answer is load18: In a diode, after the barrier potential is overcome, all that impedes the current is the      a. ohmic resistance of the p and n regions      b. bulk resistance      c. dynamic resistance of the p region      d. depletion resistanceThe correct answer is a19: How is the power dissipation of a diode calculated?      a. diode current times diode resistance

      b. diode voltage divided by diode current      c. diode voltage times diode current      d. diode current divided by diode voltageThe correct answer is c20: Most electronic troubleshooters begin by measuring      a. voltages out of the power supply      b. resistances of the diodes      c. power of the diodes      d. current out of the power supplyThe correct answer is a21: What is the data sheet specification that lists the reverse current at the maximum reverse dc rated voltage?      a. reverse breakdown      b. maximum forward current      c. maximum reverse current      d. forward breakdownThe correct answer is c22: The point of intersection which is called the Q point, represents      a. the intersection of the diode curve and the load line      b. the intersection of cutoff and the diode voltage      c. the intersection of saturation and diode current      d. the intersection of cutoff and diode currentThe correct answer is a23: The two most popular basic styles of surface-mount packages are surface mount and      a. small outline transistor      b. large outline transistor      c. surface outline diode      d. surface outline transistorThe correct answer is a24: Much of the information on a manufacturer?s data sheet is      a. necessary to understand diode circuits      b. necessary to troubleshoot diode circuits      c. obscure and of use only to circuit designers      d. necessary only to electronic techniciansThe correct answer is c25: As with many tiny surface mount devices, the determination of the PIN is obtained from      a. clues on the circuit board and schematic diagram      b. reading the numbers on the device?s underside      c. reading the color code on the device?s underside      d. reading the label stamped on the top of the deviceThe correct answer is a

CHAPTER-4 DIODE CIRCUITS

1: The half-wave rectifier has a diode in parallel with a load resistor.      a. True      b. FalseThe correct answer is b2: In electronic equipment power supplies, the transformer steps the line voltage up to higher levels that can more easily be used with semiconductor devices.      a. True      b. FalseThe correct answer is b3: The full-wave rectifier is equivalent to two half-wave rectifiers.      a. True      b. FalseThe correct answer is a4: The bridge rectifier is similar to a half-wave rectifier because it produces a half-wave output voltage.      a. True      b. FalseThe correct answer is b5: The choke-input filter is often used because of its low cost and light weight.      a. True      b. FalseThe correct answer is b6: The peak inverse voltage is the maximum voltage across the conducting diode of a rectifier.      a. True      b. FalseThe correct answer is b7: For low-voltage power supplies, the integrated circuit has been replaced by the LC filter.      a. True      b. FalseThe correct answer is b8: It is more often the case that equipment failure is caused by troubles in the power supply.      a. True      b. FalseThe correct answer is a9: A clamper is a circuit that removes either positive or negative parts of a waveform.      a. True      b. FalseThe correct answer is b10: A diode circuit used to protect a sensitive circuit is called a_____.The correct answer is limiter11: Applying an external voltage to change the reference level of a circuit is called_____.The correct answer is bias12: A_____is a circuit that adds a dc voltage to the signal?The correct answer is clamper13: If you_____a clamper and a peak detector, you get a peak-to-peak detector.The correct answer is cascade

14: Half-wave rectifier voltage produces_____current flow.The correct answer is unidirectional15: A step-up transformer will produce a secondary voltage that is_____than the primary.The correct answer is larger16: Ac ripple measurements can be most accurately made by using a(n)_____.The correct answer is oscilloscope17: The_____is the most popular rectifier circuit.The correct answer is bridge18: By using rectifier diodes and operating at 60 Hz, what type of power supply can be configured?      a. IC      b. voltage doubler      c. passive      d. clipperThe correct answer is b19: When neither end of a load resistor is grounded, the load resistor is said to be      a. open      b. shorted      c. a voltage divider      d. floatingThe correct answer is d20: Phasing dots that appear at the upper ends of the transformer?s schematic symbol mean that the dotted ends have the      a. same instantaneous phase      b. opposite instantaneous phase      c. iron core insert      d. connection for 60 Hz inputThe correct answer is a21: What is the small ac load voltage that can be measured (with an oscilloscope) at the output of a choke-input filter?      a. peak      b. ripple      c. surge      d. harmonicThe correct answer is b22: What is the term for a special kind of high frequency power supply used in computers and monitors?      a. crowbar protection      b. half-wave      c. bridge      d. switching regulatorThe correct answer is d23: The voltage that must be less than the breakdown voltage of the diode as to prevent damage to

the diode is the      a. peak inverse voltage      b. maximum diode voltage      c. reverse surge voltage      d. maximum peak voltageThe correct answer is a24: What is the type of fuse that can temporarily withstand overloads in current?      a. overload fuse      b. slow-blow fuse      c. temporary blow fuse      d. fast-acting fuseThe correct answer is b

25: A circuit that removes all the positive parts of the input signal is a      a. positive clipper      b. positive clamper      c. negative clipper      d. positive voltage doublerThe correct answer is a

CHAPTER-5 SPECIAL PURPOSE DIODES1: A zener diode is a silicon diode that operates in the active region.      a. True      b. FalseThe correct answer is b2: The zener diode must remain in the active region under all operating conditions in order for a zener regulator to hold the output voltage constant.      a. True      b. FalseThe correct answer is b3: A shorted component is equivalent to a resistance of infinity, and an open component is equivalent to a resistance of zero.      a. True      b. FalseThe correct answer is b4: Optoelectronics is the technology that combines optics and electronics.      a. True      b. FalseThe correct answer is a5: A seven-segment display contains seven rectangular optocouplers.      a. True      b. FalseThe correct answer is b6: An optoisolator combines an FET and a photodiode is a single package.      a. True

      b. FalseThe correct answer is b7: The Schottky diode has metal on one side of the junction and therefore has a large depletion layer.      a. True      b. FalseThe correct answer is b8: A varactor is also called a voltage-variable capacitance.      a. True      b. FalseThe correct answer is a9: The negative resistance of tunnel diodes is useful in oscillator circuits.      a. True      b. FalseThe correct answer is a10: The zener diode is the backbone of_____regulators.The correct answer is voltage11: _____bias is required for normal operation of a zener diode.The correct answer is Reverse12: A circuit used when the desired dc output is less than the output of the power supply is a_____regulator.The correct answer is zener13: A device which is optimized for its sensitivity to light and has a window that lets light pass through the package to the junction is a_____.The correct answer is photodiode14: The combination of an LED and a photodiode is called a(n)_____.The correct answer is optocoupler15: A_____diode has a metal such as gold or silver on one side of the junction and doped silicon on the other side.The correct answer is Schottky16: A device used for electronic tuning and often used in television and FM receivers is a(n)_____.The correct answer is varactor17: A semiconductor device that operates as a variable resistor at RF and microwave frequencies is a(n)_____diode.The correct answer is PIN18: In order to maintain a constant output voltage, the zener diode      a. must be connected to a transformer      b. must remain forward biased      c. must remain in the breakdown region      d. must be in series with a filter capacitorThe correct answer is c19: The manufacturer?s data sheet entry that lists how much the power rating of a device must be reduced is the      a. maximum power dissipation      b. reverse breakdown voltage      c. power production factor

      d. derating factorThe correct answer is d20: The basic idea of voltage regulation is that the output voltage remains the same      a. with virtually no change of input voltage      b. with considerable changes of input voltage      c. when power is turned off      d. even if a passive filter is usedThe correct answer is b21: Which of the following is not an advantage of a light-emitting diode (LED)?      a. low voltage      b. long life      c. fast on-off switching      d. costThe correct answer is d22: What type of cable is comprised of thin flexible fibers of glass or plastic that transmits light beams instead of free electrons?      a. coaxial      b. stranded copper cable      c. fiber-optic      d. wave guideThe correct answer is c23: As frequency increases, small-signal diodes are no longer able to      a. switch off fast enough      b. amplify ac signals      c. be forward biased      d. serve as active filtersThe correct answer is a24: The Schottky diode is sometimes called a      a. silicon rectifier      b. tunnel diode      c. cold-carrier diode      d. hot-carrier diodeThe correct answer is d25: A diode that is useful in frequency multiplier circuits is a      a. snap diode      b. slope diode      c. photo diode      d. zener diodeThe correct answer is a