Cherry Elex

7/27/2019 Cherry Elex

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Geronimo, Cherry MayEC52FC1

CHAPTER 1

INTRODUCTION TO SEMICONDUCTORS

1. The forces between the opposite charges form an Electric field2. What is the least accurate approximation of a diode that

can be represented by a simple switch?

The Ideal diode model

3. The best conductors are the _________ element materials Single4. Occurs when a conduction-band electron loses energy

and falls back into a hole in the valence bandRecombination

5. Refers to the fact that the region near the pn junction isdepleted of charge carriers due to diffusion across the

junction.

Depletion

6. The condition that essentially prevents current through thediode

Reverse bias

7. The absence of an electron in the valence band of anatom

Hole

8.

The removal or addition of an electron from or to a neutralatom so that the resulting atom has a net positive or negative charge.

Ionization

9. The resistance of a forward-biased diode is called the Dynamic or acresistance

10. One that has no impurities Intrinsic crystal11. Most good insulators are ________ rather than the single-

element materialsCompounds

12. To increase the number of conduction-band electrons inintrinsic silicon, ___________ impurity atoms are added.

Pentavalent

13. To increase the number of holes in intrinsic silicon, __________ impurity atoms are needed.

Trivalent

14. A ___________ material consists of silicon atom and trivalentimpurity atoms such as boron

p-type

15. A silicon material that consists of silicon atoms andpentavalent impurity atoms such as antimony.

N- type

16. What is the value of the reverse current of practical diodemodel?

0

17. Semiconductor atoms bond together in a symmetricalpattern to form a solid material called ___________.

crystal


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CHAPTER 2

DIODE APPLICATIONS

1. An open primary or secondary winding of a power supply transformer results in

0 V

2. The output frequency of a half-wave rectifier is _________to/of the input frequency Equal

3. What is the average value of the half-waverectified voltage given 25 V as its peak amplitude?

7.95 V

4. The PIV rating of the bridge diodes is __________to/than that required for the center-tapped configuration.

Less

5. Diode circuits used to clip off portions of signalvoltages above or below certain levels,

Clippers

6. The output frequency of a full-wave rectifier is ________ the input frequency

Twice

7.

A transformer is generally specified based on _____________rather than the turns ratio, Secondary voltage

8. The period of a full-wave rectified voltage is ____________ that of a half-wave rectified voltage

Half

9. The indication of the effectiveness of the filter iscalled

Ripple factor

10. Eliminates the fluctuations in the rectified voltageand produces a relatively smooth dc voltage

Filter

11. Circuit that maintains a constant dc voltage for variations in the input line voltage or in the load

Regulator

12. A type of full-wave rectifier that uses two diodesconnected to the secondary of a center-tappedtransformer

Center-tapped rectifier

13. Use clamping action to increase peak rectifiedvoltages without the necessity of increasing thetransformers voltage rating

Voltage multipliers

14. Maximum voltage appearing across the diode inreverse bias

PIV

15. Caused by the charging and discharging of thefilter capacitor

Ripple voltage

16. A systematic process of isolating, identifying, andcorrecting a fault in a circuit or system

Troubleshooting

17. Allows unidirectional current through the loadduring the entire 360 of the input cycle

Full-wave rectifier

18. Allows current through the load only during one-halfof the cycle.

Half-wave rectifier

19. Generally used because of the surge current thatinitially occur s when power is first turned on

Slow-blow type fuse

20. A figure of merit used to specify the performance ofa voltage regulator

regulation


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CHAPTER 3

SPECIAL- PURPOSE DIODES

1. Diodes that were designed to operate in reversebreakdown

Zener diode

2. A device that operates in reverse bias photodiode3. A zener diode operating in breakdown acts as a Voltage regulator 4. A positive temperature means that the zener

voltageIncreases with an increase in

temperature on decreases withdecrease in temperature.

5. A diode that always operates in reverse-bias andis doped to maximize the inherent capacitanceof the depletion region is

Laser

6. When the light-emitting diode (LED) is forward-biased, __________pass the pn junction andrecombine with____________ in the

_________material.

Electrons, holes, p-type

7. The first visible red LEDs were produced using GaAsp8. The normalized output of the visible red, yellow,

green and blue LED peaks at __________________ (nm) respectively.

660,590,540, and 460

9. Organic LEDs and LEDs produce light through theprocess of __________ and ___________ respectively.

Electrophophorescence andelectroluminescence

10. An increase in the amount of light intensityproduces an increase in

Reverse current

11. A diode that can be used as a variable-resistance device controlled by light intensity.

Photodiode

12. A diode that operates only with majority carriers Schottky diode13. A diode that takes advantage of the variable

forward resistance characteristic.PIN diode

14. No reverse leakage current Schottky diode15. Diode used in VHF and fast switching

applicationsStep- Recovery diode

16. When a PIN diode is forward-biased, it acts like a Current-controlled variableresistance

17. If a tunnel diode is placed in series with the tank circuit and biased at the center of the negative-resistance portion of its characteristic curve, a

_________ will result in the output.

Constant sinusoidal voltage

18. The tunnel diode is only used at VHF19. In a varactor diode, what happens to the

capacitance if the reverse-bias voltagedecreases?

a. Increases

20. The varactor capacitance ratio is also known as a. Tuning ratio


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CHAPTER 4

BIPOLAR JUNCTION TRANSISTORS

1. Which is the least of the three transistor currents? Base2. The ratio of the dc collector current to the dc

base current of the transistor is,

dc beta/dc current gain

3. the ratio of the dc collector current to the dcemitter current

dc alpha

4. Determine the base current given dc beta=100 ,dc alpha=0.85, and IC= 3.70mA

0.037mA

5. Nonconducting state of a transistor Cutoff6. State of a BJT in which the collector current has

reached maximum and is dependent of the basecurrent

Saturation

7. Neither the base-emitter nor the base-collector junctions are forward-biased

cutoff

8.

dc beta varies with collector current andtemperature9. h FE varies with which transistor current/s? Collector only10. Converts light energy to electrical signal Phototransistor 11. Devices used to electrically isolate circuits Optocouplers12. A key parameter in optocouplers is the CTR. CTR

stands for Current transfer ratio

13. Indication of how efficiently a signal is coupledfrom input to output

CTR

14. RF transistors are designed to operate at EHF15. What transistor category/ies uses plastic or metal

packages?

General-purpose transistors

16. To operate as an amplifier, BE junction must beforward-biased and the BC junction must bereverse-biased. This is called

Forward-reverse bias

17. In a phototransistor, what transistor current/s isproduced and controlled by light?

Base

18. Two basic package types Through-hole and surfacemount

19. The process of increasing the power, voltage, or current by electronic means.

Amplification


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CHAPTER 5

TRANSISTOR BIAS CIRCUITS

1. What biasing method is common in switchingcircuits?

Base bias

2. A Base bias in linear region shows that it is Directly dependent on dc beta3. In an emitter-feedback bias, if the collector current increases, the emitter voltage

Increases

4. What happens to the base voltage in no. 10? Increases5. In an emitter-feedback, the increase in base

voltage _________ the base current.Reduces

6. For collector-feedback bias, what provides thebias for the base-emitter junction?

Collector voltage

7. As temperature goes up in a collector-feedback circuit, DC and V BE goes _______ and __________,respectively.

Up and down

8.

Collector-feedback bias provides good stabilityusing negative feedback from Collector to base

9. Innovations in technology would allow a doublingof the number of transistors in a given space everyyear and that the speed of those transistors wouldincrease. This prediction is widely known as

Moores law

10. If an amplifier is not biased with correct dcvoltages on the input and output, it can go

___________ when an input signal is applied.

Saturation or cutoff

11. Given a voltage-divider biased BJT, determine I C given V CC , R1, R2, RC , and R E which are 10V,10kohms, 4.7kohms, 1kohm, and 470ohmsrespectively. Use DC = 100.

5.31mA

12. What is the value of V CE in no.20? 2.19 V13. If an emitter resistor is added to a base bias

circuit, what is the value of the emitter currentgiven V CC , RE, RC , and R B as 10V, 1k, 470, and180k, respectively. Use DC =100.

3.32mA

14. Calculate for V CE in no. 22 5.12 V15. If the dc beta in the preceding drops half of its

original value, find the percent change in I C .39.16%

16. What is the percent change in V CE? 27.17%17. The region along the load line including all points

between saturation and cutoffLinear region

18. A voltage divider for which loading effects canbe neglected

Stiff voltage divider

19. The base bias circuit arrangement has poor stability because its Q-point varies widely with

Dc beta

20. The purpose of biasing a circuit is to establish aproper stable ________.

Q-point

21. The process of returning a portion of a circuits Feedback


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output back to the input in such a way as tooppose or aid a change in the output

CHAPTER 6

BJT AMPLIFIERS

1. Amplifiers designed to handle small __________ signalsare referred to as small-signal amplifiers.

ac only

2. Which of the r parameters is the most important? r e 3. Determine the ac emitter resistance that is operating

with a dc emitter current of 5mA.5.0

4. If ac =h fe , ac =? h fb 5. Which of the three amplifier configurations exhibit high

voltage gain and high current gain?Common-emitter

6. An amplifier configuration which has a voltage gain ofapproximately 1, a high input resistance and currentgain,

Common-collector

7. An amplifier configuration which provides high voltagegain with a maximum current gain of 1.

Common-base

8. Which of the amplifier configurations is the mostappropriate for certain applications where sources tendto have low-resistance outputs?

Common-base

9. In a common-emitter amplifier, any change in inputsignal voltage results in

Opposite change incollector signal voltage

10. The ac voltage gain is the ratio of ac output voltage at thecollector to ac input

voltage at the base11. the reduction in signal voltage as it passes through a

circuitattenuation

12. the overall voltage gain of the common-emitter amplifier is the product of the voltage gain from base tocollector and

reciprocal of theattenuation

13. Without the bypass capacitor, the CE amplifiers emitter is no longer at ac ground. How does this affect theamplifier?

It decreases the ac voltagegain

14. The measure of how well an amplifier maintains itsdesign values over changes in temperature,

Stability

15. Swamping is a method used to minimize the effect ofthe ____________without reducing the voltage gain to itsminimum value.

ac emitter resistance

16. ___________ contains two transistors. The collectors oftwo transistors are connected and the emitter of the firstdrives the base of the second.

Darlington pair

17. _____________ consists of two types of transistors, npnand a pnp.

Complementary Darlington


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CHAPTER 7

POWER AMPLIFIERS

1. It is the product of Q-point current and voltage of atransistor with no signal input

Power dissipation

2. The ____________ of an amplifier is the ratio of the outputsignal power supplied to a load to the total power fromthe dc supply.

Efficiency

3. Which amplifier operates in the linear region for 180 deg.Of the input cycle when biased in cutoff and is in cutofffor 180 deg?

Class B

4. These amplifiers are biased to conduct for slightly morethan 180 deg.

Class AB

5. An amplifier that is generally used in Radio Frequencyapplications

Class C

6. Implemented with a laser diode Current mirror 7. An amplifier that is biased below cutoff and is normally

operated with resonant circuit loadClass C

8. The four classes of power amplifiers are classified basedon the percentage of the ____________which theamplifier operates in its ________region

Input cycle, linear

9. It is the ratio of the output power to the input power Power gain10. Product of the rms load current and the rms load

voltageOutput power

11. A type of class B amplifier with two transistors in whichone transistor conducts for one half-cycle and the other conducts for the other half-cycle

Push-pull

12. Amplifiers that are generally used in Radio FrequencyApplications.

Class C amplifiers

13. Another term for complementary Darlington Sziklai pair

18. An amplifier configuration in which the input signal iscapacitively coupled to the emitter and the output iscapacitively coupled from the collector,

Common-base

19. Which of the amplifier configurations is/are useful athigh frequencies when impedance matching is

required?

Common-base

20. The power gain of a common-base amplifier isapproximately equal to

Voltage gain

21. BJT amplifier that produces output that are a function ofthe difference between two input voltages,

Differential amplifier

22. Ideally, a diff-amp provides a very high gain for single-ended or differential signals and _____________ gain for common-mode signals.

0

23. Input signals are out of phase Differential amplifier


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14. An advantage of push-pull class B and class ABamplifiers over class A

Efficiency

15. The Q-point is at _________ at class B operation Cutoff16. Operates in the linear region where the output signal is

an amplified replica of the input signalClass A

17. Amplifiers that have the objective of delivering power toa load Power amplifers

18. When the Q-point is at the center of the ac load line, amaximum class ________ signal can be obtained.

A

19. The maximum efficiency of capacitively coupled class Aamplifier cannot be higher than

25%

20. The low efficiency of class A amplifiers limits their usefulness to small power applications that requireusually less than ________.

1 W

CHAPTER 8

FIELD EFFECT TRANSISTORS

1. FETs are preferred device in low-voltage switchingapplications; while______ transistor is generally used inhigh-voltage switching applications.

IGBT

2. What type of JFET operates with a reverse-biased pn junction to control current in the channel?

JFET

3. An n-channel universal transfer characteristic curve isalso known as

Transconductance curve

4. The change in drain current for a given change in gate-to-source voltage with the drain-to-source voltage

constant

Forwardtransconductance

5. What is the most common type of JFET bias? Self-bias6. It is a method for increasing the Q-point stability of a self-

biased JFET by making the drain current essentiallyindependent of gate-to-source voltage

Current-source bias

7. What JFET bias uses a BJT as a constant-current source? Current-source bias8. For increased Q-point stability, the value of R S in the self-

bias circuit is increased and connected to a negativesupply voltage. This sometimes called

Dual-supply bias

9. VGS varies quite a bit for JFET self-bias and voltage-divider bias but I D is much more stable with

Voltage-divider bias

10. ____________ is sometimes calleddepletion/enhancement MOSFET.D-MOSFET

11. LDMOSFET has a lateral channel structure and is a typeof

Enhancement MOSFET

12. It is an example of the conventional E-MOSFET designedto achieve higher power capability

VMOSFET

13. Following are the three ways to bias a MOSFET except Current-source bias14. The insulated-gate bipolar transistor combines which two BJT and MOSFET


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CHAPTER 9

FET AMPLIFIERS AND SWITCHING CIRCUITS

transistors that make it useful in high-voltage and high-current switching applications?

15. What are the three terminals of IGBT? Gate, collector, emitter 16. In terms of switching speed, __________ switch fastest and

_____________ switch slowest.MOSFETs, BJTs

17. In a MOSFET, the process of removing or depleting thechannel of charge carriers and thus decreasing thechannel conductivity

Depletion

18. The ratio of change in drain current to a change in gate-to source voltage in a FET

Transconductance

19. A FET is called a ______________ because of therelationship of the drain current to the square of a termcontaining gate-to-source voltage

Square-law device

20. Combines features from both the MOSFET and the BJTthat make it useful in high-voltage and high-currentswitching applications.

IGBT

21. Has a lateral channel structure and is a type ofenhancement MOSFET designed for power applications.

LDMOSFET

1. An amplifier that primarily uses only MOSFETs. Class D2. A process in which an input signal is converted to a

series of pulses with widths that varies proportionally tothe amplitude of the input signal.

PWM

3. It removes the modulating frequency and harmonicsand passes only the original signal to the output.

Low-Pass Filter

4. The voltage gain of a common-drain amplifier isalways

Slightly less than 1

5. The load resistance connected to the drain of acommon-source amplifier reduces ____________

Voltage gain

6. What is the relationship between the input resistanceof a common-gate amplifier to its transconductance?

They are inverselyproportional

7. The efficiency of a class D amplifier approaches 100%8. The input signal is applied to the gate and the output

is taken from sourceCommon-drain

9. A nonlinear amplifier in which the transistors areoperated as switches

Class D

10. A device that switches an analog signal on and off Analog switch11. Consists of two or more analog switches that connect

sample portions of their analog input signals to singleoutput in a time sequence

Analog multiplexer

12. Used in low-power digital switching circuits CMOS13. Amplifier commonly used as frequency multiplier Class C14. The least efficient amplifier Class A


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CHAPTER 10

AMPLIFIER FREQUENCY RESPONSE

15. An amplifier that is biased below cutoff Class c16. A class of amplifier that operates in the linear region

for only a small part of the input cycleClass C

17. In a class AB amplifier, if the V BE drops are notmatched to the diode drops or if the diodes are

not in thermal equilibrium with the transistors, thiscan result in

Thermal runaway

1. The frequency at which the output power drops toone-half of its midrange value

Corner frequency

2. At the critical frequencies the output voltage is 70.7%of its midrange value. What is the value of voltagegain in dB?

-3 dB

3. What is the other term for lower critical frequency? All of the above4. The condition where the gain is down 3 dB is logically

called _________ of the amplifier response-3 dB point

5. The upper and lower dominant critical frequencies aresometimes called

Half-power frequencies

6. A characteristic of an amplifier in which the product ofthe voltage gain and the bandwidth is alwaysconstant when the roll-off is -20 dB/ decade.

Gain-bandwidth product

7. Critical frequencies are values of frequency at whichthe RC circuits reduce the voltage gain to

____________ of its midrange value.

70.7%

8. An octave of frequency change is a ________ -timeschange

2

9. Which of the following has no effect on the low-frequency response?

Internal transistor capacitances

10. What is the gain that occurs for the range offrequencies between the lower and upper criticalfrequencies?

Midrange gain

11. Which of the following is not a method in frequencyresponse measurement?

Roll-off measurement

12. If the voltage gain is less than one, what is the value ofthe dB gain?

Negative

13. A plot of dB voltage gain versus frequency on semiloggraph paper

Bode plot

14. The critical frequency at which the curve breaks intoa -20dB/decade drop

Lower break frequency

15. The change in gain or phase shift over a specifiedrange of input signal frequencies

Frequency response

16. A unit of logarithmic gain measurement and iscommonly used to express amplifier response

Decibel


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CHAPTER 11

THYRISTORS

1. It is like the four-layer diode but with the added gateconnection

SCR

2. This is the maximum continuous anode current thatthe device can withstand in the conduction stateunder specifies conditions.

Average forward current

3. What bilateral thyristor functions basically like twoparallel SCRs turned in opposite directions with acommon gate terminal?

Triac

4. ____________ does not belong to the thyristor familybecause it does not have a four-layer type ofconstruction.

UJT

5. It can be used a trigger device for SCRs and triacs. UJT6. It is a type of three-terminal thyristor that is triggered

into conduction when the voltage at the anodeexceeds the voltage at the gate.

PUT

7. A region of forward bias in which the device has avery high forward resistance and is in the off state

Forward-blocking region

8. A method for turning-off the SCR that basicallyrequires momentarily forcing current through the SCRin the direction opposite to the forward conduction

Forced commutation

9. The value of gate current necessary to switch the SCRfrom the forward-blocking region to the forward-conduction region under specified conditions.

Gate Trigger Current

10. A four-layer semiconductor device that operatesessentially as does the conventional SCR except thatit can also be light-triggered.

LASCR

11. Functions basically like two parallel 4- layer diodesturned in opposite directions.

Diac

17. The lower and upper critical frequencies of anamplifier can be determined using the _____________ method by applying a voltage step to the input of theamplifier and measuring the rise and fall times of theresulting output voltage

Step-response method

18. The coupling an bypass capacitors of an amplifier affect the _________ frequency response: high or low Low

19. The internal transistor capacitances affect the _________ frequency response: high or low

High

20. Two frequency response measurement Frequency/amplitude andstep

21. The Miller input and output capacitances for a BJTinverting amplifier depends on

Voltage gain

22. When dB is negative, it is usually called_______ Attenuation


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12. A diac with gate terminal Triac13. A four-terminal thyristor that has two gate terminals

that are used t trigger the device on and offSilicon Controlled Device

(SCS)14. A type of three-terminal thyristor that is triggered into

conduction when the voltage at the anode exceeds

the voltage at the gate.

Programmable UnijunctionTransistor

(PUT)15. The characteristic of a UJT that determines its turn-onpoint

Standoff-ratio

16. The four-layer diode is also called Shockley diode17. The region that corresponds to the on condition of the

SCR where there is forward current from anode tocathode through the very low resistance of the SCR

Forward_ conductionregion

18. The SCR can only be turned on using its _________ terminal

Gate

19. Acts as the trigger source in the LASCRs Light20. A thyristor that conducts when the voltage across its

terminals exceeds the breakover potential

4-layer diode

21. Basic methods of for turning off an SCR Anode current interruptionand forced commutation

CHAPTER 12

THE OPERATIONAL AMPLIFIER

1. The measure of an amplifiers ability to reject common -modesignals

CMRR

2. It is the typical value of input offset voltage in the ideal case. 0 V3. It is the dc current required by the inputs of the amplifier to

properly operate the first stage.Input bias current

4. It is the resistance viewed from the output terminal of the op-amp

Output impedance

5. The total resistance between the inverting and noninvertinginputs

Differential inputimpedance

6. Differential impedance is measured by determining thechange in ___________ for a given change in differential inputvoltage.

Bias current

7. Common temperature coefficient for the offset current 0.5nA/C8. Functions of negative feedback in an op-amp Stabilize gain and

increase frequencyresponse

9. The voltage gain of an op-amp with external feedback Closed-loopvoltage gain

10. A special case of the noninverting amplifier where all of theoutput voltage is fed back to the inverting input by a straightconnection

Voltage-follower configuration

11. The value of the frequency at which the gain steadilydecreases to a point where it is equal to unity

Unity-gainfrequency


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Or unity gainbandwidth

12. It is always equal to the frequency at which the op- ampsopen- loop gain is unity or 0 dB.

Gain-bandwidthproduct

13. The relative angular displacement of a time-varying function

relative to a reference.

Phase shift

14. The three terminals of the basic op-amp not including power and ground

Inverting input,noninverting input,

and output15. It has the highest input impedance and the lowest output

impedance of the three amplifier configurationsVoltage-follower

16. The _________ of an op-amp equals the upper criticalfrequency.

Bandwidth

17. Two types of op-amp input operation. Differential modeand common-

mode18. A ____________ differentiator uses a capacitor in series with the

inverting input.Ideal

19. An ideal op-amp has ___________ value for voltage gain,bandwidth, and input impedance.

Infinite

20. What should be the output voltage of an op-amp when thedifferential input is zero

Zero

21. The ideal op-amp has __________ output impedance Zero22. The three basic op-amp configurations Inverting,

noninverting, andvoltage follower

23. The closed-loop voltage gain is _________ than the open-loopvoltage gain. (more or less)

Less

24. Does the gain of an op-amp decreases or increases asfrequency increases above the critical frequency

Decreases

25. Devices such as the diode and the transistor which areseparate devices that are individually packaged andinterconnected in a circuit with other devices to form acomplete, functional unit.

Discretecomponents

26. Most op-amps operate with how many dc supply voltage? 2(positive and

negative)27. Datasheets often refer to the open-loop voltage gain as the

______________ Large-signalvoltage gain


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CHAPTER 13

BASIC OP-AMP CIRCUITS

1. A common interfacing process often used when a linear analogsystem must provide inputs to a digital system.

A/D conversion

2.

Method of A/D conversion that uses parallel comparators tocompare the linear input signal with various reference voltagesdeveloped by a voltage divider

Flash

3. Produces an output that is proportional to the rate of change ofthe input voltage

Differentiator

4. The difference between the UTP and the LTP Hysteresis voltage5. Used to generate pulse waveform from the sine wave output of

the audio generator.Voltage

comparator 6. When the output is at the maximum positive voltage and the input

exceeds UTP, the output switches to the _________ negativevoltage

Maximum

7. Uses a capacitor in the feedback path which is open to dc. Thisimplies that the gain at dc is the open-loop gain of the op-amp.

Practical integrator

8. Gives an op-amp noise immunity Hysteresis9. Used to detect positive and negative voltages by connecting a

fixed reference voltage source to the inverting input of a zero-leveldetector.

Nonzero-Leveldetection

10. A good example of hysteresis Thermostat11. A comparator with three trigger points Schmitt Trigger 12. The output of Schmitt trigger is Pulse waveform13. In a comparator with output bounding, what type of diode is used

in the feedback loop?Zener

14. Necessary components for the design of a bounded comparator Rectifier and zener diodes

15. Type of circuit that uses comparators Nonzero-leveldetector

16. Variations of the basic summing amplifier Averaging andscaling amplifier

17. Differentiation of a ramp input produces a step output with anamplitude proportional to the _________

Slope

18. Another term for flash Simultaneous19. Integration of a step input produces a ramp output with the slope

proportional to the _________ Amplitude


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CHAPTER 14

SPECIAL PURPOSE OP-AMP CIRCUITS

1. Provides dc isolation between input and output Isolation amplifier 2. Ratio of the output current to the input voltage Transconductance

3.

Transconductance is __________ of an OTA Gain4. A comparator with hysteresis where the input voltage is largeenough to drive the device into its saturated states

Schmitt trigger

5. The ______________ of a number is the power to which the basemust be raised to get that number.

Logarithm

6. An amplifier that produces an output that is proportional to thelogarithm of the input.

Log amplifier

7. Used in applications where it is necessary to have an outputcurrent that is controlled by an input voltage.

Voltage-to-currentconverter

8. The circuit used to detect the peak of the input voltage and storethat peak voltage on a capacitor.

Peak detector

9.

The exponent to which the base e must be raised in order to equala given quantity. Natural logarithm

10. In an OTA, transconductance varies with _________. Bias current11. Amplifiers that are often used in HF communication systems,

including fiber optics, for processing wide dynamic range signals.Log and antilog

amplifiers12. The key characterisctic of an instrumentation amplifier CMRR13. The voltage gain of instrumentation amplifier is set by a Resistor 14. The log amplifier may use the ___________ junction of a BJT in the

feedback loopBase-emitter

15. The main purpose of an instrumentation amplifier is to amplify _____ signals that are riding on _____ common-mode voltages.

small, large

16. The ___________ of an OTA is the input voltage times thetransconductance

Output current

17. The operation of log and antilog amplifiers is based on the __________ characteristics of a pn junction

Nonlinear (logarithmic)

18. A log amplifier has a pn junction in the feedback loop, and anantilog amplifier has a pn junction in __________ with the input

Series

19. In a peak detector, an op-amp is used as a __________ to charge acapacitor through a diode to the peak value of the input voltage.

Comparator

20. A basic instrumentation amplifier is formed by three op-amps and ________ resistors, including the gain setting resistor.

Seven (7)

21. An oscillator that can be either amplitude or pulse modulated bythe signal from the input amplifier

High-frequencyoscillator


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CHAPTER 15

ACTIVE FILTERS

1. The ___________ of a band-pass filter is the ratio of the center frequency to the bandwidth.

Quality factor

2.

An active filter category that rejects the frequencies within acertain bandwidth and passes frequencies outside the bandwidth Band-stop filter

3. A filter response characteristic that provides a very flat amplituderesponse in the passband and a roll-off rate of -20dB/decade/pole

Butterworthcharacteristic

4. Each filter in a cascaded arrangement is called ___________. Stage or section5. It is one of the most common configurations for two-pole filter. It is

also known as a voltage-controlled voltage source filter.Sallen-Key

6. A filter required to get a third-order low-pass response. This is doneby cascading a two-pole Sallen-key low-pass filter and a single-pole low-pass filter

Three-pole filter

7. Each additional filter in a cascaded arrangement adds _______dBto the roll-off rate

-20 dB

8. The rate of decrease in gain, below or above the criticalfrequencies of a filter.

Roll-off

9. Technology that enables the tracking and/or identification ofobjects.

Radio FrequencyIdentification

(RFID)10. Four categories of active filters Low-pass, high-

pass, band-pass,and band-stop

11. Low-pass bandwidth is equal to Cutoff frequency12. Filters with the Bessel characteristic are used for filtering ________

waveformsPulse

13. Two common types of band-stop filters. Multiple-feedback and state-variable

14. Tiny, very thin microchips with memory and a coil antenna RFID tags15. This type of tag does not require batteries. The tag is inactive until

powered by the energy from the electromagnetic field of an RFIDreader

Passive RFID tag

16. This type of tag is powered by a battery and is capable ofcommunicating up to 100ft. Or more from the RFID reader.

Active RFID tag

17. Another type of tag that is a paper labelled with printing with theRF circuitry and antenna embedded in it.

Smart label

18. The property of selecting signals with certain selected frequencieswhile rejecting signals with other frequencies.

Selectivity

19. A pole is simply a circuit with how many resistor or capacitor? 120. The damping factor affects the filter response by negative

feedback action. True/falseTrue

21. The more poles a filter has , the faster its roll-off rate is True22. Another term for state-variable filter Universal active

filter 23. Two methods of determining a filters response by measurement Discrete point


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measurement andswept frequency

measurement24. Produces a constant amplitude output signal whose frequency

increases linearly between two preset limits.Swept frequency

generator

25. How many poles does a Sallen-Key high pass filter have? 226. The center frequency of a state variable resistor is set by the

_______ circuits in both integrators,RC

CHAPTER 16

OSCILLATORS

1. A circuit that produces a periodic waveform on its output with onlythe dc supply voltage as an input

Oscillator

2. The two major classifications for oscillators are feedback oscillatorsand _______________.

Relaxationoscillators

3. Characterized by the condition wherein a portion of the outputvoltage of an amplifier is fed back to the input with no net phaseshift resulting in a reinforcement of the output signal

Positive signal

4. An amplifier gain of greater than ________ will cause the oscillator to limit both peaks of the waveform

100

5. The most widely used type of RC feedback oscillator for frequencies up to about 1 MHz

Wien-bridge

6. Quarts is one type of crystalline substance found in nature thatexhibits a property called ________

Piezolelectric effect

7. This type of LC feedback oscillator uses transformer coupling tofeed back a portion of the signal voltage. It is sometimes called atickler oscillator

ArmstrongOscillator

8. Devices that produce more than one output function Functiongenerators

9. A relaxation oscillator whose frequency can be changed by avariable dc control voltage

Voltage-controlledoscillator

(VCO)10. ___________ oscillators include the Colpitts, Clapp, Hartley,

Armstrong, and crystal-controlledSinusoidal LC

11. ___________ oscillators include the Wien-bridge, phase-shift, andtwin-T

Sinusoidal RC

12. This type of oscillator used an LC circuit in the feedback loop toprovide the necessary phase shift and to act as a resonant filter that passes only the desired frequency of oscillation

Colpitts Oscillator

13. It is a variation of the Colpitts but with an additional capacitor inseries with the inductor in the resonant feedback circuit

Clapp Oscillator

14. He invented the Hartley oscillator and the Hartley transform, amathematical analysis method , which contributed to thefoundations of information theory

Ralph Vinton LyonHartley

15. Similar to Colpitts except that the feedback circuit consists of two Hartley oscillator


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series inductors and a parallel capacitor 16. The most stable and accurate type of feedback oscillator uses a

piezoelectric _________ in the feedback loop to control frequency.Crystal

17. The lowest frequency at which a crystal is naturally resonant. Fundamentalfrequency

18. For higher frequencies, the crystal must be operated in this mode Overtone mode19. A type of relaxation oscillator because its operation is based onthe charging and discharging of a capacitor

Square-Waveoscillator

20. A two-state device whose output can be at either a high voltageor a low voltage level

Flip-flop

21. For initial start-up, the voltage gain around the feedback loop mustbe greater that

1(one)

22. The feedback signal in an Armstrong oscillator is derived by ________ coupling

Transformer

23. A type of RC feedback oscillator which used two T-type RC filters

used in the feedback loop, one has a low-pass response and theother has high-pass response

Twin-T oscillator

24. A loop is created in which the signal sustains itself and a continuoussinusoidal output is produces

Oscillation

25. The phase shift around the feedback loop must be effectively ________ degrees to sustain the state of oscillation

0

26. The voltage gain around the closed feedback loop must be equalto _________ to sustain state of oscillation.

1(unity)

27. The product of the amplifier gain and the attenuation of thefeedback circuit

Voltage gain

28. He was involved in the development of oscillators and vacuumtube push-pull amplifiers at Western Electric in the early 1900

Edwin H. Colpitts

29. The frequency in a VCO can be varied with a _______ controlledvoltage

Dc

CHAPTER 17

VOLTAGE REGULATORS

1. The percentage change in the output voltage for a given changein the input voltage

Line regulation

2. The percentage change in output voltage for a given change inload current

Load regulation

3. Occurs when the internal power dissipation becomes excessiveand the temperature of the device exceeds a certain value

Thermal Overload

4. An electronic circuit that maintains an essentially constant outputvoltage with a changing input voltage or load current

Regulator

5. Typical of three-terminal IC regulators that provide a fixed negativeoutput voltage.

79XX

6. An example of a three-terminal positive regulator with an LM317


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adjustable output voltage.7. Negative output counterpart of the LM317 LM3378. A universal device that can be used with external components to

provide step-up, step-down, and inverting operation78S40

9. A voltage regulator in which the control element operate as a

switch

Switching regulator

10. Two basic types of linear regulators are Series and shunt11. In linear series regulator, the control element is a transistor in

_______ with the loadSeries

12. In linear shunt regulator, the control element is a transistor in _______ with the load.

Parallel

13. A change in input voltage does not significantly affect the outputvoltage of a regulator. (true/false)

True

14. Can be used as a current source when an application requiresthat a constant current be supplied to a variable load.

Three-terminalregulator

15. Amplitude modulation is a ____________________process Multiplication

16. is one method used to overcome the bandwidth limitation of thetelephone system so that digital data can be sent over the phonelines.

FSK

CHAPTER 18

COMMUNICATIONS1. The circuit that recovers the modulating signal form 455 kHz

intermediate frequency.Detector

2. Picks up all the radiated signals and feeds them into the RFamplifier.

Antenna

3. Provides a dc level out of the detector that is proportional to thestrength of the received signal

Automatic GainControl(AGC)

4. It brings the high frequency audio signals back to the proper amplitude relationship with the lower frequencies

De-emphasis Network

5. Removes any unwanted variations in the amplitude of the FMsignal as it comes out of the IF amplifier and produces aconstant amplitude FM output at the 10.7 MHz intermediatefrequency

Limiter

6. A feedback circuit consisting of a phase detector, a low passfilter, and a VCO

PLL

7. The range of frequencies over which the PLL can acquire lock with an incoming signal

Capture range

8. The angle that defines whether a light ray will be reflected or refracted as it strikes a surface.

Critical Angle

9. A linear device that produces an output voltage proportional tothe product of two input voltages

Four-quadrantMultiplier

10. An optical characteristic of a material that determines thecritical angle.

Index of refraction

11. A device for down-converting frequencies in a receiver system Mixer


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12. The RF amplifier, mixer, and local oscillator are tunedsimultaneously so that the LO frequency is always 455 kHz abovethe incoming RF signal frequency.

Gang tuning

13. A special case of the multiplier that is realized by simply applyingthe same voltage to both inputs by connecting the inputs

together.

Squaring circuit

14. Reverse modulation Demodulation15. The process of varying a parameter of a carrier signal with an

information signal.Modulation

16. Most VCOs employed in PLLs operate in the principle of ____________ using the varactor diode as a voltage-variablecapacitor.

Variable reactance

17. The range of frequencies over which the PLL can maintain lock Lock range or tracking range

18. Independent of the bandwidth of the low-pass filter becausewhen the PLL is in lock, the difference in frequency is zero or avery low instantaneous value the falls well within the bandwidth.

Hold-in range

19. Uses light pulses to transmit information through fiber-opticcables.

Fiber optics

20. Fiber optic cable in which the diameter of the core is fairly largerelative to the diameter of the cladding.

Multimode step index

21. Fiber optic cable in which the diameter core is very smallrelative to the diameter of the cladding.

Single-mode stepindex

22. Fiber optic cable in which the diameter of the core is fairly largerelative to the diameter of the cladding.

Multimode gradedindex

23. A linear multiplier can be used as a _________ detector Phase24. The output of a linear multiplier is the ________ of the inputs and

a scale factor Product

25. The IF in a standard AM receiver is 455 kHz26. A form of amplitude modulation in which the carrier is

suppressedBalanced modulation

27. Another term for balanced modulation Suppresses-carrier modulation

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