Chapter 1 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A sine wave is described as v(t) = 30 V sin (350t). This means that the angular frequency of this waveform is A) 350 Hz B) 5.75 rad/s C) 350 rad/s D) 173 rad/s
1)
2) Name an example of a non-linear amplifier output. A) An amplified audio signal C) A square wave
2)
B) A sinusoidal waveform D) An output signal from a electric guitar
3) A vector must meet the following conditions: A) It must represent an electrical quantity B) It must have a quantity of voltage and a period of time C) It must have volume and direction D) It must have magnitude and direction
3)
4) If the second stage of two cascaded amplifiers has its input resistance decrease, what will happen to the magnitude of the output signal? A) load voltage will decrease but load current will increase B) it will decrease C) there will no change D) it will increase
4)
5) Which term does not define ac resistance? A) Reactance C) Small signal resistance
5)
B) Dynamic resistance D) Bulk resistance
6) Sampling is the process of? A) Testing gain by measuring output on a oscilloscope B) Rejecting high or low signals C) Breaking down an analog wave into time slices D) Troubleshooting by inputting a signal
6)
7) What converts some physical quantity into an electrical quantity to be measured? A) Ammeter B) Voltmeter C) Sensor D) Transducer
7)
8) The no-load output voltage of a complex linear circuit is measured as 600 mV. When a 220 ▲ load is connected, the load voltage is found to be 489 mV. What is the Thevenin resistance of the circuit? A) 102 ▲ B) 179 ▲ C) 75▲ D) 50 ▲
8)
9) What is log 1000? A) 2
9)
B) 4
C) 1
D) 3
10) The amount of power dissipated by a resistor connected to an ac source is defined by? A) P = Vp x Ip B) P = .707Vp x .707Ip C) P = Vp/Ip D) None of the above
1
10)
11) If a waveform repeats every 1ms, what is the frequency? A) 100KHz B) 100 Hz C) 10KHz
D) 1KHz
11)
12) A linear component is one in which an increase in current is proportional to the applied voltage as given by Ohm's law. Which of the following is an example of a linear component? A) Transistor B) Capacitor C) Diode D) Resistor
12)
13) If the power gain of an amplifier is said to be 3:1, what is the dB gain? A) 3 log 10dB B) 10 log 3 dB C) 30 dB
13)
D) 4.8 dB
14) A digitized signal is... A) Difficult to store for reproduction B) Close to, but not exactly the same as the analog original C) Considered to contain more noise than an analog signal D) An exact replica of the analog original
14)
15) The period of a waveform is? A) The measure of the height of a waveform B) The time a periodic wave takes to complete one cycle C) Another name for cps D) The reciprocal of time
15)
16) Analog and digital signals are also referred to as? A) Steady and constant C) Continuous and discrete
16)
B) Small signal and large signal D) Constant and varied
17) What is the symbol used to represent angular frequency? A) B) C)
D)
17)
18) The average value of a sine wave is computed by? A) Converting the negative portion of the waveform to positive and averaging B) Multiplying the peak to peak value by 6.28 then averaging C) Adding the positive going peaks to the negative peaks and dividing by two D) Dividing the peak value by .707
18)
19) In order to simplify a circuit, one can replace a complicated two-terminal linear circuit with an ideal voltage source and a series resistance. What is this process called? A) Ohm's law B) Thevenin's theorem C) Norton's theorem D) Equivalent circuit analysis
19)
20) Which component is considered to be analog? A) A two-pole switch C) An infrared pulser
20)
B) None of the above D) A potentiometer
21) Load lines terminate on the X and Y-axis of a graph. What do the terminal points represent? A) Maximum and minimum current in a circuit B) Saturation and cutoff C) A short and open load condition of a circuit D) All of the above
2
21)
22) Analog circuits are typically not used for which of the following applications? A) Signal mixing B) Decoding C) Transforming voltage to current D) Waveshaping
22)
23) The unit of measure for frequency is? A) Hertz C) Both A & B
23)
B) Cycles per second (CPS) D) Neither A nor B
24) Which of the following statements are true regarding amplifiers? A) Amplifiers cannot be cascaded B) An amplifier can amplify voltage beyond it's supply voltage C) An ideal amplifier produces no noise or distortion D) Amplifiers do not amplify power, only current or voltage
24)
25) Which statements are true about sinusoidal waveforms? A) Sinusoidal waveforms do not repeat B) They are a composite of fundamental and harmonic frequencies C) A sinusoidal waveform has no fundamental frequency D) A sinusoidal waveform does not contain harmonics
25)
26) AC resistance is the ratio of the change in voltage divided by a change in current and can be seen on a characteristic curve. Which statement about characteristic curves is true? A) analog components cannot be represented by a characteristic curve B) ac characteristic curves are always linear C) The ac resistance depends on what point on the IV characteristic curve the measurement is made D) dc characteristic curves always have the same slope
26)
27) Electron Theory suggests that: A) Electrons actually move from a negative toward a positive voltage B) Electrons and protons are responsible for current flow C) Electrons move from a positive toward a negative voltage D) Current flow is not a component of electron movement
27)
28) What is the third odd harmonic of a 1KHz square wave? A) 3KHz B) 7KHz C) 5KHz
D) 9KHz
28)
29) How do spectrum analyzers measure signals? A) In the frequency domain B) By converting a digital signal to an analog format C) In the time domain D) By digitizing an analog signal
29)
30) In order to simplify a circuit, one can replace the source voltage with a current source in parallel with the simple resistance of a circuit. What is this method of circuit analysis? A) Circuit analysis B) Ohm's law C) Thevenin's theorem D) Norton's theorem
30)
3
Answer Key Testname: CHAPTER 1 1) C 2) C 3) D 4) B 5) A 6) C 7) D 8) D 9) D 10) B 11) D 12) D 13) D 14) B 15) B 16) C 17) D 18) A 19) B 20) D 21) D 22) B 23) C 24) C 25) D 26) C 27) A 28) A 29) A 30) D
4
Chapter 2 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) If the forward bias is less than the barrier potential, what condition is the diode in? A) The diode will function as a 1k resistor B) The diode will actually conduct some small amount ofcurrent C) The diode will conduct heavily because the barrier potential is greater than the forward bias D) The diode will not conduct until forward bias is greater than the barrier potential
1)
2) Which best describes a conducting forward-biased diode? A) Positive cathode, negative anode VF = .2 volts
2)
B) Negative cathode, positive anode VF = 0.7 volts
C) Positive cathode, negative anode VF = 10 volts
D) Negative cathode, positive anode VF = .2 volts
3) What is the difference between a full-wave rectifier usig a center-tapped transformer and a bridge full-wave bridge rectifier using a transformer with the same turns ratio? A) Center-tapped rectifier will deliver twice the output voltage B) Center-tapped rectifier will deliver half the voltage that the bridge will deliver C) No difference, except small design configuration difference D) Three diodes
3)
4) Seven-segment displays are arranged as A) common-anode C) both A and B
4)
B) common-cathode D) common-cathode except for the decimal
5) An open diode in a bridge rectifier circuit will produce what type of waveform? A) Half-wave with decreased ripple B) Full-wave with decreased ripple C) Half-wave with increased ripple D) Full-wave with increased ripple
5)
6) Describe the effect of a capacitor-input filter on the output of a rectifier. A) Any size capacitor will smooth out voltage variations as long as it is in series with Rl B) Large capacitor in parallel with R L will reduce large voltage variations
6)
7) In a conductor, the energy levels of the conduction and valence band A) are the same B) are negative C) are very close in value D) overlap
7)
8) The majority carriers in the p region of a diode A) are electrons B) a much less in number than the majority carriers in the n region C) a much fewer in number than the majority carriers in the n region D) are holes
8)
C) Capacitor in series with load resistor will absorb large voltage variations D) Small capacitor in parallel with the load resistor will absorb current variations
1
9) What factor always effects a rectifier's output voltage? A) Diode voltage drop B) Type of rectifier C) The load resistance D) All of the above
9)
10) What denotes the maximum voltage a diode can withstand when reverse-biased? A) Reverse bias B) Peak forward-bias voltage C) Reverse breakdown D) Peak inverse voltage
10)
11) What is a rectifier? A) An electronic device that converts ac into pulsating dc B) An electronic device that converts pulsating ac into dc C) An electronic device that converts pulsating dc into ac D) An electronic device that converts audio signals to radio frequency
11)
12) Doping is the process of adding impurities to pure semiconductor material. Impurities define the majority and minority carriers in a semiconductor. Which of the following statements is true? A) Trivalent impurities cause electrons to be the majority carriers B) Pentavalent impurities cause holes to be the majority carriers C) Pentavalent impurities add one extra hole to the covalent bond D) Trivalent impurities cause holes to be the majority carriers
12)
13) What is the purpose of a current-limiting resistor in a diode circuit? A) A current-limiting resistor is only necessary if it is reverse biased B) The resistor prevents the diode from becoming reverse-biased C) The resistor will increase the PIV rating of the diode D) A properly biased diode is like a short circuit, therefore a resistor provides a voltage drop
13)
14) Assume that a 7805 regulator has a measured no-load output of 5.26 volts and a full-load output of 5.19 volts. What is the load regulation expressed as a percentage? A) 1.18% B) 1.19% C) 1.28% D) 1.35%
14)
15) OLEDs produce light through what process? A) oragaluminescence C) optical resonance
15)
B) electrophosphorescence D) electroluminescence
16) The offset resistance model of a reverse-biased diode can be approximated as A) a reverse polarity voltage source in parallel with a resistor B) a high value resistor in parallel with an open switch C) a high value resistor in series with a closed switch D) an open switch
16)
17) Assume the input ripple to a 7812 regulator is 80mV. What is the output ripple if the ripple rejection ratio is 72 dB. A) 20.1 µV B) 0.2 mV C) 2.01 µV D) None of the above
17)
18) What circuit would change the reference level of an ac signal? A) A limiter B) A clamper C) A clipper D) None of the above
18)
2
19) Photodiodes... A) Are similar to photoresistors C) Both A & B
B) Work only when forward-biased D) Neither A or B
19)
20) Using an ohmmeter to check a diode, what indicates the diode is likely good? A) Low resistance regardless of how the leads are connected B) High resistance measured regardless of how the leads are connected C) Low resistance measured only with positive lead on cathode and negative lead on anode D) Low resistance measured only with positive lead on anode and negative lead on cathode
20)
21) Name the two most common semiconductor materials. A) Silicon and germanium B) Gallium and Arsenide C) Germanium and carbon D) Gallium and silicon
21)
22) The following diode works well in conjunction with the resonant frequency formula to perform tuning functions: A) Varactor B) Pn Junction C) Schottky D) Zener
22)
23) Which one of the following devices is roughly equivalent to a diode? A) A pressure regulator B) A one-way valve C) A spring D) None of the above
23)
24) What output can be expected in a diode limiter circuit in which the input is a pure sinusoidal wave? A) Only one peak will be reduced to the value of the diode voltage drop B) The positive and negative peaks will be reduced by the voltage drop of the diode C) The positive and negative peaks will be reduced to the value of the diode voltage D) Only one peak will be reduced by the value of the diode voltage drop
24)
25) What can be said regarding the energy level of an electron? A) Electrons in the shell closest to the nucleus of an atom have the highest energy level B) All electrons have the same energy level C) Electrons in the outermost shell have the highest energy level D) Electrons exhibit energy characteristics only in the presence of protons
25)
26) What can be said about the depletion region in a diode? A) The depletion region shrinks as the diode is reverse biased B) The depletion region acts as an insulator and the dielectric value is proportional to barrier potential C) The depletion region size is independent of barrier voltage D) The size of the depletion region is inversely proportional to barrier potential
26)
27) What is a general characteristic of all Light Emitting Diodes? A) LED's can emit any color in the spectrum B) The amount of light output is proportional to forward current C) All LED's have the same voltage drop D) All LED's emit infrared radiation
27)
3
28) When recombination occurs, an electron A) loses energy C) drops into a hole
B) drops into the valence band D) all of the above
28)
29) What statement best describes the action of a zener diode? A) When the diode is biased into saturation, it tends to regulate voltage because of it's bulk resistance B) Zener diodes are used mostly in tuning circuits C) Zener diodes regulate voltage levels below their minimum forward bias D) Zener diodes regulate voltage upon exceeding reverse breakdown voltage
29)
30) Which of the following is the best arrangement for a 7800 series IC regulator? A) Small capacitor at the input and large capacitor on the output B) Large capacitor on the input and small capacitor on the output C) Equivalent capacitors on both the input and output D) Any of the above will have the same effect
30)
4
Answer Key Testname: CHAPTER 2 1) B 2) B 3) B 4) C 5) C 6) B 7) D 8) B 9) D 10) D 11) A 12) D 13) D 14) D 15) B 16) B 17) A 18) B 19) A 20) D 21) A 22) A 23) B 24) A 25) C 26) B 27) B 28) D 29) D 30) B
5
Exam
Chapter 3
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) An npn BJT has the following values meausred: Vc = 8.3 V, VE = 1.1 V and Vcc = 18 V. The value of
1)
2) Regarding transistor operation in general: A) a large base current controls a small collector current B) a small base current controls a large collector current C) emitter current controls collector current D) collector current controls base current
2)
3) A cutoff transistor has: A) VCE cannot be calculated at cutoff C) VCE = 0 V
3)
VCE must be A) Cannot be deternined, it depends on the value of . B) 8.6 V C) 9.4 V D) 27.4 V
B) VCE = VCC D) none of the above
4) Which bias circuit is found chiefly in integrated circuit applications? A) base bias B) emitter bias C) voltage divider bias D) collector feedback bias
4)
5) Voltage divider bias provides a high degree of stability as long as what principle is observed? A) IR2 is ten times greater than IB. B) RL is smaller than R1 + R2 C) IB = IR2 D) Either a or b
5)
6) What is the primary difference between a Common Base and Common Emitter circuit? A) where the output is taken from B) emitter ground C) bias circuit D) where the input signal is fed into the amplifier
6)
7) In a Common-Emitter amplifier A) the output signal is taken from the emitter B) the output is taken from the collector C) the emitter is the reference for the input signal D) the emitter is always above ground potential
7)
8) Transistor data sheets provide what information? A) electrical characteristics C) thermal characteristics
B) maximum ratings D) all of the above
1
8)
9) Regarding Darlington Pairs, which statement is true? A) the emitter of the first transistor drives the base of the second B) high input impedance C) high output impedance D) both a and b
9)
10) A transistor in saturation is equivalent to what condition? A) an open switch B) a closed switch C) a or b depending on where voltage is measured D) none of the above
10)
11) If the base of a transistor is open, the voltage at the collector will be A) VCC/2 B) it dpends on the beta of the transitor C) VB D) VCC
11)
12) With respect to a collector characteristics curve A) only one base current can be represented on a characteristic curve B) beta cannot be calculated from the curve C) after (Vce) reaches 0.7 volts collector current is close to it's full value D) changing base currents have little effect on collector current
12)
13) Name the condition whereby collector current reaches its peak. A) Beta max B) Beta min C) cutoff
13)
D) saturation
14) DC beta refers to: A) the ratio of emitter current to collector current B) the ratio of base current to collector current C) a transistor's gain characteristics D) both a and b
14)
15) If VCE is 13 V and Vcc is 15 V, this transitor is
15)
A) approaching saturation C) approaching cutoff
B) a pnp transistor D) properly biased
16) VCC = 12 volts, RC = 1k, determine the load line IC and VCE intercepts A) IC = IB = 12mA and VCE = 12m volts B) IC = 1.2mA and VCE = 12m volts C) IC = 12mA and VCE = 12 volts D) IC = .012mA and VCE = 1.2 volts
16)
17) In order for a transistor to operate properly: A) the (BE) junction is reverse-biased C) (BC) bias is unimportant
17)
B) the (BE) junction is forward-biased D) (BE) and (BC) bias are always the same
18) With respect to the input signal of an amplifier A) the output is always out of phase B) the output is always in phase C) the base and collector signal are always out of phase D) the base and collector signals are always in phase
2
18)
19) How can we ensure that a Common Emitter amplifier has a high input impedance? A) add a swamping resistor B) always calculate the circuit parameters using a known Bdc C) add a resistor that appears in series with the source D) all of the above
19)
20) Regarding the Common Emitter amplifier A) the output is at the emitter B) the input is applied to the base C) the input and output is measured at the base D) both a and b
20)
21) An npn transitor is biased using collector feedback. Rc = 2.2 k = 250. Solve for the value of base current. A) 3.16 µA B) 31.6 µA
and R B = 220 k . Vcc = 25 V and
C) 7.9 mA
D) 214 µA
22) Collector feedback bias works on what principle? A) rising collector currents tend to attenuate base current B) falling collector currents tend to attenuate base current C) base current will always remain constant D) positive feedback adds to collector current 23) IIf the collector of a transistor is open, the voltage at the emitter will be A) VCC/2 B) VB - 0.7 V C) VB
21)
22)
D) VCC
23)
24) What makes a base-biased circuit a good choice for switching applications? A) simple, single resistor bias circuit B) calculate saturation and cutoff without considering beta C) both a and b D) none of the above
24)
25) Which amplifier configuration is the least often used? A) Darlington Pair B) Common Emitter C) Common Collector D) Common Base
25)
26) A quad dual-inline package indicates A) four individual circuits in four packages C) four transistors on one chip
26)
B) an integrated circuit amplifier D) two circuits with four pins
27) Compared to the collector and emitter regions A) the base region is heavily doped B) the base region is lightly doped C) the base and emitter are always doped the same D) the base region is doped the same
27)
28) The term bipolar means: A) the use of both holes and electrons as carriers B) polarity is unimportant C) diodes only D) electrons make up the majority carriers
28)
3
29) Coupling capacitors are used because A) they provide an closed path for AC signals B) they prevent feedback noise C) they amplify inputs D) they provide isolation between bias and signal sources
29)
30) Common-Collector amplifiers are preferred to drive low impedance loads because A) low input impedance buffers output B) CC amplifiers have high voltage gain C) CC output impedance is low D) all of the above
30)
4
Answer Key Testname: CHAPTER 3 1) B 2) B 3) B 4) B 5) A 6) D 7) B 8) D 9) D 10) B 11) D 12) C 13) D 14) D 15) C 16) C 17) B 18) C 19) D 20) D 21) B 22) A 23) B 24) C 25) D 26) C 27) B 28) A 29) D 30) C
5
Chapter 4 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A FET amplifier has values of gm = 2000 µS, RD = 2 k , and RS = 500 amplifier is A) 2
B) 10
. The votlage gain of this
C) 4
1)
D) 1
2) Pinch-off voltage refers to A) value of drain-source voltage at which drain current is minimum B) value of drain-source voltage at which drain current remains constant C) value of drain-source voltage at which drain current is maximum D) none of the above
2)
3) Sample-and-hold circuits are used in A) multiplexing C) RF circuits exclusively
3)
B) analog-to-digital converters D) all of the above
4) An FET's constant current region A) covers a relatively wide drain-source voltage range B) depends on gate-source voltage as shown on drain curve C) is between pinch-off voltage and breakdown region on characteristic curve D) all of the above
4)
5) A switched capacitor is used to emulate A) a vari-cap B) an inductor
C) a diode
5)
6) CMOS uses A) dual-polarity supplies C) E-MOSFETs and D-MOSFETs
B) n-channel and p-channel D-MOSFETs D) n-channel and p-channel E-MOSFETs
D) a resistor
6)
7) E-MOSFETs are generally used for switching circuits because A) They have high RDS B) They are very linear
7)
8) The transconductance curve is not a straight line implying that the relationship between the output current and input voltage is not linear. This means that A) A FET can add distortion to the input signal B) FETs require compensation circuits C) The input current is the mirror image of the output current D) both a and c
8)
9) Drain characteristic curves show A) voltage value where constant current begins B) the ohmic region C) the constant current range for ID D) all of the above
9)
C) They have very low RDS
D) The have high off current
1
10) Which type of MOSFET can be operated with either positive or negative gate-source voltage? A) E-MOSFET B) D-MOSFET C) B-MOSFET D) Any of the above
10)
11) As the gate-source voltage becomes more negative A) drain-source voltage decreases B) drain current remains unchanged by negative gate-source bias C) drain current decreases D) drain current increases
11)
12) A transconductance curve is A) always a straight line B) exactly the same representation as a drain curve C) a graph of drain current versus gate-source voltage D) both a and c
12)
13) How does the gate control current in a FET? A) restricting current flow by changing channel width B) restricting free electron flow by way of hole current C) the drain controls current flow D) magnetic attraction of p-channel holes
13)
14) What are the three terminals of the FET? A) emitter, gate, drain C) emitter, base, drain
14)
B) drain, base, source D) source, drain, gate
15) What best describes the physical properties of a FET? A) three equal regions are combined by silicon impurities that inhibit current flow B) two narrow channels are connected by a lead called the drain C) two narrow channels are connected by a gate D) a narrow conducting channel is connected by two leads called the source and drain
15)
16) A cascode amplifier has A) a common-drain in series with a common-gate B) any of the above C) a common-emiiter in series with a common-collector D) a common-source in series with a common-gate
16)
17) For an n-channel JFET, if pinch-off voltage equals five volts then VGS(off) A) equals minus five volts B) equals beta times five volts C) equals five volts D) equals zero volts
17)
18) In general, MOSFET's A) are mostly used in switching circuits B) can be fabricated in much higher densities than BJT's C) produce simpler circuits than BJT's D) all of the above
18)
2
19) Increasing gate-source voltage A) narrows channel width thereby reducing drain current B) widens channel width thereby reducing gate current C) narrows channel width thereby increasing drain current D) widens channel width thereby increasing drain current
19)
20) Cutoff voltage refers to A) the value of drain-source voltage that make Id=0 B) the value of gate-source voltage that make Id=0 C) the value of gate-source voltage that makes Id saturate D) none of the above
20)
21) Which are characteristics of self-biased FETs? A) the gate is always at zero volts B) they operate on feedback principles C) only require a single-source power supply D) all of the above
21)
22) Which best describes a Field-Effect transistor? A) a voltage-controlled device in which voltage at the gate controls current through the device B) a current-controlled device in which current at the gate controls voltage at the drain C) a voltage-controlled device with a low input impedance. D) a current-controlled device in which the current at the gate controls current at the drain
22)
23) VGS(off) for an E-MOSFET A) is always negative C) is always lower than for a D-MOSFET
23)
B) is always positive D) can be either positive or negative
24) AN IGBT can be viewed as A) a current-controlled JFET C) a current-controlled MOSFET
B) a voltage-controlled BJT D) a low-input impedance MOSFET
24)
25) What makes a FET an excellent first stage amplifier? A) very low input impedance B) very high input impedance C) low noise D) both a and c
25)
26) Which bias circuit forces the gate to a positive voltage? A) gate-bias B) voltage divider C) self-bias
26)
27) What is meant by transconductance? A) Maximum current flow of a device C) dynamaic FET impedance
D) source-bias
B) the output for a given input D) it is the measure of an FET's efficiency
28) Which of the following MOSFET bias circuits is the preferred method for D-MOSFET's? A) source bias B) voltage divider C) current source bias D) zero-bias
3
27)
28)
29) The normal bias condition for an n-channel FET is A) negative drain, positive source, reverse-biased gate to source B) positive drain, negative source, reverse-biased gate to source C) negative drain, positive source, forward-biased gate to source D) positive drain, negative source, forward-biased gate to source
29)
30) What is an advantage of MOSFET's over BJT's in power applications? A) MOSFETs are somewhat immune to thermal runaway B) MOSFETs have lower on resistance C) BJT's have lower on resistance D) both a and c
30)
31) Dual-gate MOSFETs A) can be used in AGC circuits C) have lower input capacitance
31)
B) have better high-frequency response D) all of the above
32) One difference between MOSFETs and JFETs is A) Some MOSFETs have no channel until they are biased B) MOSFETs use only positive gate-source voltages C) JFETs produce non-linear transconductance curves D) All of the above
32)
33) Input resistance of a FET is very high due to A) gate-source junction is reverse-biased B) forward-biased junctions have high impedance C) drain-source junction is reverse-biased D) none of the above
33)
4
Answer Key Testname: CHAPTER 4 1) C 2) B 3) B 4) D 5) D 6) D 7) C 8) A 9) D 10) B 11) C 12) C 13) A 14) D 15) D 16) D 17) A 18) D 19) A 20) B 21) D 22) A 23) B 24) B 25) D 26) B 27) B 28) D 29) B 30) D 31) D 32) A 33) A
5
Chapter 5 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A decoupling network consists of A) a low-value resistor in series with a capacitor that is tied to ground B) a capacitor in series with a resistor that is tied to ground C) an inductive filter D) a low-pass filter at the supply rail
1)
2) The principle advantage of IC amplifiers over discreet component amplifiers is A) much higher gain B) do not have to provide heat sinking C) high reliability and low cost D) all of the above
2)
3) The efficiency of a capacitor-coupled class A amplifier is A) usually about 10% B) the ratio of the power supplied to the load to the power delivered by the dc supply C) always less than 25% D) all of the above
3)
4) To provide gain stability in direct coupled amplifiers A) use collector feedback B) use negative feedback C) use a common-base amplifier configuration D) none of the above
4)
5) Clipping can be caused by A) biasing too close to cutoff C) biasing too close to cutoff
B) too high an input signal D) all of the above
5)
6) Class A amplifiers A) are small signal amplifiers only B) always operate in the non-linear region of the ac load line C) always operate within the linear region D) are used as power amplifiers only
6)
7) How can standing waves be eliminated? A) use the shortest possible line B) terminate the line with a proper capacitive load C) make the line a multiple of the wavelength D) terminate the line with a proper resistive load
7)
8) Power gain A) equals load voltage squared divided by load resistance B) is the ratio of the power delivered to the load versus input power C) both a and b D) none of the above
8)
1
9) PWM is used in A) complimentary symmetry amplfiers C) class C amplifiers
B) class D amplifiers D) all of the above
9)
10) Several voice channels transmitted on one coax cable in both directions at the same time using A) frequency separation filters B) high-frequency filters C) shunt LC filters D) low-frequency filters
10)
11) Class C amplifiers can have efficiencies of A) close to 75% C) very close to 100%
11)
B) better than 50% D) close to 90%
12) Where are capacitors used in direct-coupled amplifiers? A) at the input and output B) input only C) output only D) direct coupled amplifiers do not use capacitors
12)
13) Capacitor coupling is desirable because A) it allows the gain of one stage to couple to the next B) bias from one stage can be isolated from the bias circuit of another stage C) capacitors block dc and pass ac D) all of the above
13)
14) To compute the overall gain of an amplifier which parameter does not need to be known? A) input resistance of each stage B) voltage gain of each stage C) configuration of each stage D) output resistance of each stage
14)
15) If you see an amplifier with a tank circuit in the collector, chances are it is a A) transformer-coupled amplifier B) class C amplfier C) low-frequency power amplfier D) complimentary symmetry amplfier
15)
16) To provide bias stabilization in direct coupled amplifiers A) use a common-base amplifier configuration B) use collector feedback C) use negative feedback D) none of the above
16)
17) Class B amplifiers A) split the input signal between the output transistors B) require two transistors C) are more efficient than class A D) all of the above
17)
18) Skin effect refers to the fact that A) noise can enter a circuit through the surface of a circuit trace B) current migrates away from the outer surface of a conductor at higher frequencies C) current migrates to the outer surface of a conductor at higher frequencies D) at higher frequencies transmission lines become effective capacitors
18)
2
19) What does the "cure" for noise problems depend on? A) the type of noise B) the source of noise C) the path of noise into the circuit D) all of the above
19)
20) If the Q of a tuned amplifier increases A) the center frequency shifts slightly lower C) the bandwidth increases
20)
B) the gain at the center frequency inceases D) all of the above
21) Neutralization is the process of what? A) adding capacitance to cancel out inductance B) using out-of-phase feedback to cancel out positive feedback C) shorting-out feedback using coupling transformers D) all of the above
21)
22) What is the effect of capacitance at high frequencies? A) capacitance can limit the speed of a digital pulse B) internal capacitance reduces the effectiveness of active devices C) capacitance appears as a low impedance path for high frequency signals D) all of the above
22)
23) During signal processing, the RF signal is usually converted to a lower frequency by mixing the RF with an oscillator. This new frequency is known as the A) reference frequency B) drop-down frequency C) internal frequency D) intermediate frequency
23)
24) The second stage of a two-stage amplifier has values of Rin = 10 k and Av(NL) = 40. Rout for the first stage is 2 k and the load on the second stage is 1 k . If Vout for the first stage is 100 mV, what is the value of load voltage? A) 3.7 V B) 44 mV C) 444 mV D) 368 mV
24)
25) The formula for characteristic impedance for high frequency transmission lines shows A) impedance is proportional to shunt capacitance B) line length is not a factor C) line length is the primary factor D) impedance is proportional to series inductance
25)
26) If you wanted to impedance match an amplifier to a load you would most likely use A) it doesn't matter, the coupling method has no bearing on impedance B) capacitor coupling C) transformer coupling D) direct coupling
26)
27) Name one method of reducing stray capacitance on printed circuit boards. A) always use the same value capacitors B) use swamping resistors when possible C) capacitors should have short lead length D) all of the above
27)
3
28) Which of the following is not a means of reducing oscillations and noise in a circuit? A) provide multiple grounding points B) tie the supply rails to ground at each stage C) use shielded wire where possible D) narrow the bandwidth of the circuit
28)
29) AGC, or automatic gain control A) reduces gain on large signals C) is proportional to input signal strength
29)
B) amplifies small signals D) all of the above
30) Two or more transistors can be connected together to enhance the performance of an amplifier. Each transistor that amplifies the signal is considered what? A) a section B) a partition C) a division D) a stage
30)
31) Why does the first transistor circuit in an amplifier need to be designed for low noise operation? A) the first transistor includes low noise filters B) high noise operation is designed in the last transistor circuit C) because small signals can easily be obscured by noise D) all of the above
31)
32) In general, radio frequencies are A) 530 kHz to 88 MHz C) frequencies from 10KHz to about 300GHz
32)
B) frequencies from 100 kHz to 100 GHz D) frequencies from 1KHz to about 10KHz
33) The quality factor of a resonant circuit measures A) the ratio of the resonant frequency to bandwidth B) the minimum energy stored in a circuit compared to the energy gain C) the ratio of Xc to XL D) the circuit gain
33)
34) Assume that the second stage of a multistage amplifier is changed from a BJT to a JFET. Assume that the output resistance and gain of the FET stage is the same as the BJT stage it replaced. What affect, if any, will this have on the output of the multistage amplifier? A) current gain will decrease B) voltage gain will decrease C) voltage gain will increase D) there will be no change
34)
35) Transformers are used to couple amplifier stages because A) they can be used in tuned circuits B) they are inexpensive C) transformers are good current amplifiers D) they easily pass ac and dc
35)
36) The final stage of a class D amplfier is A) a low-pass filter C) a MOSFET
B) a comparator D) a high-pass filter
36)
37) How can noise enter a circuit? A) through the power supply C) fluorescent lighting
B) from within the circuit D) all of the above
38) Transformer coupling is not widely applied to low frequency design due to A) size B) cost C) both a and b 4
37)
D) neither a or b
38)
Answer Key Testname: CHAPTER 5 1) A 2) C 3) D 4) B 5) D 6) C 7) D 8) C 9) B 10) A 11) A 12) D 13) D 14) C 15) B 16) C 17) D 18) C 19) D 20) B 21) B 22) D 23) D 24) C 25) B 26) C 27) C 28) A 29) D 30) D 31) C 32) C 33) A 34) C 35) A 36) A 37) D 38) C
5
Chapter 6 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What specifies how much current is required to operate the first stage? A) offset current drift B) input offset current C) input bias current D) slew rate 2) An inverting amplfier has values of Rin = 1.1 k , Rf = 2.2 k and Zout = 75 A) 2.42 k B) 76 k C) 2.2 k 3) Large signal voltage gain refers to A) a voltage follower C) open loop gain
1)
. The value of Zin is D) 1.1 k
B) voltage feedback D) closed loop gain
2)
3)
4) The measure of an amplifier's ability to reject common signals on both inputs is called A) common-mode amplification rate B) common-mode rejection C) rate of rejection D) common rejection
4)
5) What defines the maximum rate of change in output voltage for a given change in input voltage? A) slew ratio B) slew rate C) differential change ratio D) none of the above
5)
6) In an op-amp the output stage is usually A) a class D amplifier C) a push-pull class B amplifier
6)
B) a class A amplifier D) none of the above
7) What is the primary method used to control open-loop gain? A) negative feedback B) positive feedback C) ground one input D) use input resistors
7)
8) What is the total resistance between the inverting and non-inverting input? A) offset impedance B) differential input impedance C) total impedance D) common mode input impedance
8)
9) An op-amp has a differential gain of 500 and a common-mode gain of 0.15. This means that the CMRR is A) 75 B) 3333 C) 0.0003 D) 1111
9)
10) The voltage gain of an op amp with negative feedback is called A) beta B) open-loop gain C) closed-loop voltage gain D) feedback reduction
10)
11) Name the three common terminals of a typical op amp. A) Input, output, V+ B) inverting input, non-inverting input, output C) V+, V-, output D) Input, output, V-
11)
1
12) Negative feedback is important because A) it generates higher open-loop gain B) it reduces the op amps power requirements C) it allows the amplification of larger input signals without clipping D) all of the above
12)
13) Without negative feedback A) op-amp bandwidth is very limited B) gain is very high C) input voltages easily drive an op amp into no-linear operation D) all of the above
13)
14) An important feature of op amps is A) no latch-up C) input offset nulling
14)
B) short-circuit protection D) all of the above
15) A differential amplifier A) amplifies the difference between the inputs B) amplifies the difference between the input and output C) amplifies the sum of the inputs D) none of the above
15)
16) If Rf opens in a non-inverting amplifier A) it is usually driven into saturation C) the gain is unity
16)
B) the gain increases D) there is no output
17) What parameter defines how much VOS changes for each degree change in temperature?
17)
18) What is the resistance between each input and ground? A) differential input impedance B) total impedance C) common-mode input impedance D) offset impedance
18)
19) What kind of amplifier is configured such that a portion of the output is applied back to the non-inverting input through a feedback resistor? A) non-inverting amplifier B) class AB amplifier C) inverting amplifier D) none of the above
19)
20) The range of input voltage that will not cause output voltage clipping or distortion is called A) common-mode output voltage range B) common-mode input voltage range C) input voltage limit D) output voltage range
20)
21) An op-amp circuit that has a gain of unity is most likely a A) inverting amplifier B) voltage follower C) non-inverting amplifier D) all of the above
21)
22) A practical op amp has A) high input impedance C) zero output impedance
22)
A) input offset voltage drift C) slew rate
B) nothing D) none of the above
B) high voltage gain D) both a and b 2
23) If the CMRR' of an op-amp is 65 dB, the common-mode rejection ratio is A) 3.25 B) 65,000 C) 1778 24) In an op-amp A) the voltage amplifier is usually class A C) the voltage amplifier is usually class B
D) 3557
B) the voltage amplifier is usually class AB D) none of the above
23)
24)
25) Lowering the value of the feedback resistor in an inverting amplfier will A) decrease the bandwidth B) decrease the gain C) lower the output impedance D) all of the above
25)
26) If two out of phase signals are applied to the inputs of a differential amplifier it is operating in A) common rejection mode B) differential mode C) single-ended mode D) common mode
26)
27) An ideal op amp has A) zero output impedance C) infinite voltage gain
27)
B) infinite input impedance D) all of the above
28) The resistance viewed from the output terminal to ground is called A) output impedance B) bias impedance C) offset impedance D) all of the above
28)
29) The ratio of op-amp output voltage to input voltage with no feedback is called A) open loop gain B) voltage gain C) 1output gain D) closed loop gain
29)
30) If Rf opens in an inverting amplifier A) the gain is unity C) there is no output
B) the gain increases D) it is usually driven into saturation
30)
31) Which amplifier has the highest input impedance? A) inverting C) differential
B) non-inverting with feedback D) voltage follower
32) What is the difference between input bias currents? A) input offset current C) input current
B) bias current differential D) slew rate
31)
32)
33) Negative feedback A) subtracts a portion of the output from the noninverting input B) adds a portion of each input to the output C) adds a portion of the output to the inverting input D) is in phase with the input
33)
34) A small dc voltage at the output when no difference input is applied is called A) input offset current B) input offset voltage C) output impedance D) slew rate
34)
3
35) What kind of amplifier is configured such that a portion of the output is applied back to the inverting input through a feedback network? A) inverting amplifier B) a voltage follower C) non-inverting amplifier D) both a and b
4
35)
Answer Key Testname: CHAPTER 6 1) C 2) D 3) C 4) B 5) B 6) C 7) A 8) B 9) B 10) C 11) B 12) C 13) D 14) D 15) A 16) A 17) A 18) C 19) D 20) B 21) B 22) D 23) C 24) A 25) B 26) B 27) D 28) A 29) A 30) D 31) D 32) A 33) A 34) B 35) D
5
Chapter 7 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Bandwidth is increased when A) open-loop gain is reduced by negative feedback B) input levels are decreased C) open-loop gain is reduced by positive feedback D) critical frequency is changing
1)
2) To eliminate unwanted oscillations A) use capacitive coupling at inputs C) check ground paths
B) add bypass capacitors to power supplies D) all the above
3) Closed-loop gain is determined by A) external components C) output current times input offset current
B) input signal devided by Rf D) amplifier transconductance
4) A Bode plot of an op amp proves A) gain is constant C) gain is dependent on the input signal
B) gain is frequency-dependent D) none of the above
2)
3)
4)
5) The critical frequency formula for an RC network proves A) fc is inversely proportional to the square of R and C B) fc is inversely proportional to the root of R and C C) fc is inversely proportional to R and C D) fc is iproportional to R and C
5)
6) Open-loop gain A) varies widely amongst op amps C) is generally not listed on data sheets
6)
B) is nearly identical for all op amps D) is set at 200,000
7) For instability to occur A) loop-gain must be less than one C) loop-gain must be greater than one
B) negative feedback must occur D) none of the above
8) Above 1MHz an op amp approaches A) open-loop gain B) unity gain
C) about 60dB
D) about 80dB
9) Each RC network can produce up to how much phase shift? A) -90 degrees B) +90 degrees C) -180 degrees
D) +45 degrees
10) If you increase the value of Rin for an inverting amplfier A) the bandwidth decreases B) the closed loop gain increases C) the bandwidth increases D) the open-loop gain increases
1
7)
8)
9)
10)
11) Open-loop gain is also referred to as A) small signal gain C) large-signal gain
B) beta D) small signal voltage ratio
11)
12) In order to achieve precise control of gain and bandwidth, op amps are configured in A) cascaded closed amplifiers B) open-loop configuration C) cascaded open-loop amplifiers D) closed-loop configuration
12)
13) What is the phase margin of an amp with a phase shift of 180 degrees? A) 90 degrees B) 180 degrees C) minus 180 degrees D) zero
13)
14) Positive feedback A) occurs when the output is in phase with the input B) can cause oscillations C) occurs when the output is 360 degrees out of phase with the input D) all of the above
14)
15) Determine the Aol at 1 kHz if fc(ol) = 50 Hz. and Aol(mid) = 150,000 A) 7491
B) 20
C) 9950
15) D) 7500
16) An op-amp can be represented by a A) a gain element is in series with a high-pass RC filter B) a gain element with negative feedback C) a gain element is in series with a low-pass RC filter D) a differential inverting amplifier
16)
17) The propagation delay from input to output in an op-amp causes A) phase shift B) current lag C) differential
17)
18) Feed forward compensation uses a capacitor to A) increase slew rate C) bypass the first stage
D) voltage lag
B) introduce a lag between input and output D) short oscillations to ground
19) The point where gain equals 0dB is A) unity-gain bandwidth C) open-loop gain intercept
B) either intercept D) closed-loop gain intercept
20) A disadvantage of phase-lag compensation: A) decreased bandwidth C) increased bandwidth
B) reduced gain D) none of the above
21) High gain with no external components.is A) open-loop gain B) a differential amplifier used as a summing amp C) closed-loop gain D) the definition of a comparator
2
18)
19)
20)
21)
22) An op amp that has more than one critical frequency is called A) differential amp B) comparator C) compensated op amp D) uncompensated op amp
22)
23) The amount of phase shift between the intput and output signal of an op-amp operating at the critical frequency is A) 45 degrees B) -45 degrees C) -180 degrees D) 90 degrees
23)
24) Closed-loop gain is A) the voltage gain with positve feedback applied B) the voltage gain of an op amp with external feedback C) the power gain D) the voltage gain of an op amp with inverting feedback
24)
25) The roll-off rate for this type of op amp is the same as a single RC network. A) uncompensated op amp B) differential amp C) compensated amp D) decade amplifier
25)
26) In general, the bandwidth equals A) Vout/Vin B) Point where gain is 3dB more than at the midrange frequency C) fcu - fcl
26)
27) Open-loop gain is calculated by what formula? A) Vin/Vout C) Vout/Vin
27)
D) Vin - Vout
B) Beta × Vin D) None of the above
28) An amplifier has a gain of 40 and a gain-bandwidth product of 60 kHz. The unity gain bandwidth is A) 2.4 MHz B) 15 MHz C) 240 kHz D) 1.5 kHz
28)
29) In order for an amplifier to be stable A) the closed loop gain curve must intercept the open loop gain gain when the slope is -40 dB/decade B) the closed loop gain curve must intercept the open loop gain gain when the slope is -20 dB/decade C) the open-loop gain should equal the close loop gain D) none of the above
29)
30) Open-loop gain is set by A) external components B) internal design C) both internal design and external components D) none of the above
30)
3
Answer Key Testname: CHAPTER 7 1) A 2) D 3) A 4) B 5) C 6) A 7) C 8) B 9) A 10) C 11) C 12) D 13) B 14) D 15) A 16) C 17) A 18) C 19) A 20) A 21) A 22) D 23) B 24) B 25) C 26) C 27) C 28) A 29) B 30) B
4
Exam
Chapter 8
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which op-amp circuit simulates the mathematical operation that finds the area under a curve? A) an operator B) an integrator C) an implementor D) a differentiator
1)
2) A constant current source A) delivers a load current that remains constant when input voltage decreases B) delivers a load current that remains proportional to load resistance C) delivers a load current that remains constant when the load resistance changes D) all the above
2)
3) An unwanted voltage or current fluctuations are defined as A) eddy current B) noise C) hysteresis D) none of the above
3)
4) An op-amp circuit has a diode and resistor in the feedback circuit and a capacitor tied to ground. This is most likely a A) precision rectifier B) peak level detector C) bounded integrator D) window comparator
4)
5) The output of a summing amplifier is saturated regardless of the input level. The most likely fault is A) Rf is shorted B) one of the input resistors is shorted C) the inverting input is shorted D) one of the input resistors is open
5)
6) To establish a reference voltage of 10.2 V off a 15 V supply, a 2.2 k is connected in series with a A) 4.7 k resistor B) 8.6 k resistor C) 5.1 k resistor D) 3.3 k resistor
6)
7) Output bounding A) can limit both positive and negative outputs B) is a process of limiting the output range of an amplifier C) uses zener diodes D) all the above
7)
8) An op amp with the inverting input grounded or connected to a reference voltage is most likely A) a zero-level detector B) a comparator C) an integratorf D) both a and b
8)
9) A Schmitt trigger A) reduces erratic output signals due to noise B) is a comparator with hysteresis C) filters unwanted voltage or current fluctuations D) all of the above
9)
1
10) The output of a summing amplifier is saturated regardless of the input levels. The most likely failure is a A) an open input resistor B) shorted feedback resistor C) open feedback resistor D) a shorted inverting input
10)
11) How is an averaging amplifier designed? A) set the ratio R/Rf equal to the reciprocal of the number of inputs B) set the ratio Rf/R equal to the number of inputs C) set the ratio Rf/R equal to the reciprocal of the number of inputs D) set the ratio R/Rf equal to the number of inputs
11)
12) A summing amplifier A) algebraically adds any number of inputs B) algebraically adds two inputs C) algebraically adds the difference between two inputs D) none of the above
12)
13) An op amp circuit that employs a capacitor in the feedback circuit is called A) an implementor B) an integrator C) an operator D) a differentiator
13)
14) A summing amplifier with weighted input values is called a(n) A) integrator B) n-input adder C) subtractor
D) scaling adder
14)
15) Two comparators arranged such that voltage levels between two prescribed limits are detected are known as what type of a circuit? A) threshold comparator B) detector window C) threshold detector D) window comparator
15)
16) A circuit that produces an inverted output which approximates the rate of change of the input function is called a(n) A) Differentiator B) A/D converter C) Integrator D) D/A converter
16)
17) A comparator with hysteresis has the following resistors in the feedback circuit. R1 = 5 k = 10 k . If the maximum output voltage is 12 V, the value of the UTP is A) 2 V B) 8 V C) 6 V D) 4 V
and R2
17)
18) A comparator has a 5.1 V zener in the feedback circuit. If the anode is connected to the output the maximum positve output is A) -0.7 V B) +5.8 V C) +5.1 V D) +0.7 V
18)
19) Ia a zener is connected to the inverting input of an op-amp and a source voltage is connected to the non-inverting input this circuit is most likely A) a window comparator B) a non-zero level detector C) a bounded comparator D) both b and c
19)
2
20) In order to make a comparator less sensitive to noise, a technique incorporating positive feedback known as what is used? A) hysteresis B) lower threshold limiting C) upper threshold limiting D) none of the above
20)
21) A comparator generally operates in what condition? A) a comparator usually functions in either saturation or cutoff B) a comparator operates in the linear region C) a comparator usually functions in positive or negative saturation depending on input voltage D) all of the above
21)
22) An op amp circuit that employs a capacitor in the input circuit is called A) an operator B) a differentiator C) an integrator D) an implementor
22)
23) A typical ADC board contains A) an integrator C) a summing amplifier
23)
B) a comparator D) all the above
24) Input noise can be defined as: A) only unwanted voltage fluctuations B) input voltage levels in the 20Hz to 30KHz range C) unwanted current and voltage fluctuations on the input D) input voltage levels in the 200Hz to 30KHz range
24)
25) A/D conversion is A) the process of limiting the output range of a comparator B) a process to convert a digital code to analog sequence C) a circuit that produces an inverted output D) a process whereby information in analog form is converted into digital form
25)
26) In an ideal op amp has a +/-12 volt supply and a reference voltage of 2 volts on the inverting input. What would the output look like with a +/-5 volt sinusoidal input on the non-inverting input? A) the output would be a +/-5 volt sine wave B) the output would be a square wave C) the output would be a +/-2 volt sine wave D) the output would be an inverted replica of the input
26)
27) A scaling adder is used as a four-input analog-to-digital converter. If the 22 input resistance is 16 , what is the value of the 2 3 resisttor?
27)
28) A current to voltage converter A) converts a fixed input current to a sine wave output B) converts a variable input current to a proportional output C) converts a current sine wave input into a dc output voltage D) all of the above
28)
A) 256 k
B) 4 k
C) 8 k
3
D) 32 k
29) A circuit that produces an inverted output which approximates the area under the curve of the input function is called a(n) A) comparator B) integrator C) differentiator D) none of the above
29)
30) Zener diodes can be used in the feedback circuit to limit a comparator output. What is this method called? A) binding B) level saturation limitation C) output bounding D) threshold limiting
30)
4
Answer Key Testname: CHAPTER 8 1) B 2) C 3) B 4) B 5) B 6) A 7) D 8) D 9) D 10) C 11) C 12) A 13) B 14) D 15) D 16) A 17) B 18) D 19) B 20) A 21) C 22) B 23) D 24) C 25) D 26) B 27) C 28) B 29) B 30) C
5
Chapter 9 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A low-pass version of this filter uses two capacitors and two resistors A) Sallen-Key low-pass filter B) single-pole filter C) second order cascaded filter D) fourth order cascaded filter
1)
2) Op-amp circuits that pass certain selected frequencies while rejecting signals outside this range are called A) amplifiers B) converters C) filters D) processors
2)
3) Other than this, the basic parameters for high-pass and low-pass filters are the same A) the number of poles are different B) the role of the resistor and capacitor are reversed C) inverting and non-inverting inputs are reversed D) all the above
3)
4) This filter circuit passes all signals lying within a band between a lower-frequency limit and an upper-frequency limit A) band-pass B) high-pass C) low-pass D) pass band
4)
5) This circuit significantly attenuates all frequencies below the critical frequency and all frequencies above the critical frequency are passed A) high-pass filter B) low-pass filter C) band-pass filter D) active filter
5)
6) A Sallen-Key filter with a Butterworth response must have a damping factor of A) 1.414 B) 1 C) 2 D) 0.586
6)
7) Filters are usually categorized by A) the maximum output frequency B) how the output reacts to changes in input frequency C) response quality D) the ratio of input current to frequency
7)
8) In a multiple-feedback notch filter the input is applied to A) the input capacitor B) the inverting input C) the non-inverting input D) both inputs
8)
9) In a cascaded bandpass filter the input signal must be applied to A) the high-pass filter B) the higherst order filter C) the low-pass filter D) either a or b, it doesn't matter
9)
1
10) Discrete point measurement and swept frequency measurement are two methods of A) determining the average input signal of an active filter circuit B) determining a filter circuit's response C) determining a filter circuit's attenuation D) all of the above
10)
11) In general, the output from a passive high-pass filter is taken A) across the filter capacitor B) across the filter resistor C) either depending on the phase of the input D) none of the above
11)
12) High-pass filters can be cascaded in order to produce A) higher order gain response B) slower roll-off rates C) faster roll-off rates D) increased noise attenuation
12)
13) This circuit consists of a summing amplifier and two op amp integrators A) state-variable band-pass filter B) cascaded four pole active filter C) sallen-key filter D) all the above
13)
14) Filters of this type exhibit a linear phase response A) chebychev C) bessel
B) butterworth D) none of the above
14)
15) A 3rd order high-pass filter has a rolloff rate of A) -20 dB per octave C) -20 dB per decade
B) -60 dB per decade D) -30 dB per decade
15)
16) One method of achieving a higher roll-off rate is to A) attenuate output signal to increase bandwidth B) cascade filters C) attenuate input signal to increase bandwidth D) all of the above
16)
17) In an RC network, what determines the critical frequency? A) the value of the resistor B) the value of the capacitor C) both a and b D) none of the above
17)
18) In general, the output from a passive low-pass filter is taken A) across the filter capacitor B) across the filter resistor C) either depending on the phase of the input D) none of the above
18)
19) Filters with this type of response are maintain a very flat amplitude in the passband. A) the butterworth characteristic B) the bessel characteristic C) the chebycheb characteristic D) all the above
19)
2
20) This is the ratio of the center frequency to the bandwidth of a band-pass filter A) quality factor B) rejection ratio C) critical frequency D) frequency ratio 21) An active filter can be designed to have which type of response characteristic? A) butterworth B) bessel C) chebychev
20)
D) all of the above
21)
22) An active low-pass filter has a 2.2 k resistor and a 10 nF capacitor connected to the inverting input. The critical frequency for this filter is A) 7.32 kHz B) 7.23 kHz C) 1.38 kHz D) 8.51 kHz
22)
23) This active filter is considered the opposite to a band-pass filter A) band reject filter B) notch filter C) band-stop filter D) all of the above
23)
24) A bandpass filter has a Q of 4.6 and a BW of 3.45 kHz. The center frequency is A) 750 kHz B) 15.9 kHz C) 750 Hz D) 2Cannot be determined, you need one of the critical frequencies
24)
25) The range of frequencies that are not attenuated by a filter are referred to as the A) pass band B) low-pass frequency C) cutoff frequency D) band stop
25)
26) Active filters have an advantage over passive filters because A) the input signal is not attenuated as it passes through the filter B) the filters are not affected by the load C) active filters provide gain D) all the above
26)
27) The critical frequency of the basic high-pass filter occurs when A) Xc exceeds R B) XL = Xc C) XL = R
27)
D) Xc = R
28) In a state-variable filter, the Q is set by A) the feedback resistors in the second integrator B) the feedback resistor from the second integrator the summing amplifier C) the feedback resistors in the first integrator D) any of the above
28)
29) The damping factor determines A) response ratio C) gain of a circuit
B) response characteristic of a circuit D) none of the above
29)
30) A fourth-order configuration A) has four poles C) both a and b
B) uses two op amps D) none of the above
3
30)
Answer Key Testname: CHAPTER 9 1) A 2) C 3) B 4) A 5) A 6) A 7) B 8) D 9) D 10) B 11) B 12) C 13) A 14) C 15) B 16) B 17) C 18) A 19) A 20) A 21) D 22) B 23) D 24) B 25) A 26) D 27) D 28) C 29) B 30) C
4
Exam
Chapter 10
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Name two conditions for positive feedback A) phase shift zero and gain slightly less than one B) phase shift equals zero degrees and gain slightly more than one C) 180 degree phase shift and gain slightly greater than one D) 180 degree phase shift and gain slightly less than one 2) Rext = 4.7 k and C = 0.47 µF. The pulse width of the one-shot is A) 13.9 ms B) 139 µs C) 720 ms
1)
D) 2.43 ms
2)
3) In order for a 555 timer to produce a duty cycle of less than 50 % A) the resistor must be larger than the capacitor in the timing circuit B) it must have a diode connected between the reset and trigger terminals C) the capacitor must be larger than the resistor in the timing circuit D) it must have a diode connected between the discharge and trigger terminals
3)
4) An LC fedback osciillator that uses two series inductors in the feedback path is called a A) Clapp oscillator B) Inductive oscillator C) Hartley oscillator D) transformer-coupled oscillator
4)
5) Oscillators are circuits that generate a periodic waveform to perform A) control functions B) communication functions C) timing functions D) all of the above
5)
6) This type of oscillator uses an RC circuit and generates a waveform that is generally non-sinusoidal A) triangle wave oscillator B) relaxation oscillator C) sine wave generator D) none of the above
6)
7) A relaxation oscillator whose frequency can be changed by a variable dc control voltage is called a A) variable frequency oscillator B) voltage-controlled oscillator C) tunable oscillator D) all of the above are components of the described oscillator
7)
8) A term characterizing having no stable state is A) vibrator B) astable
8)
C) one-shot
9) This type of oscillator uses three RC networks A) phase-shift oscillator C) positive feedback oscillator
B) wein-bridge D) relaxation oscillator
10) Name the required oscillator input A) pulse/clock signal C) sample waveform
B) dc supply input D) all the above
1
D) monostable
9)
10)
11) Feedback oscillators operate with A) negative feedback C) positive feedback
B) both positive or negative feedback D) only positive dc supplies
12) A fundamental part of the wein-bridge oscillator is A) the positive feedback circuit C) the lead-lag network
B) zero phase shift D) all of the above
13) Name the two major classifications of oscillators A) sine wave and synchronous wave C) relaxation and feedback
B) digital pulse and analog D) sine wave and square wave
14) Sinusoidal RC oscillators include A) phase shift oscillators C) wein-bridge oscillator
B) twin-t oscillators D) all of the above
15) This device has only one stable state A) an astable multivibrator C) a one-shot
B) a monostable multivibrator D) both a and c
11)
12)
13)
14)
15)
16) The JFET in a JFET stabilized Wien-bridge oscillator function as A) a voltage divider B) a voltagecontrolled oscillator C) a voltage-controlled resistor D) all of the above
16)
17) The capacitors in a the feedback network of a Colpitts oscillator are C1 = 0.22 µF and C2 = 0.022 µF. If the inductor is equal to 1.1 mH the output frequency of the oscillator is A) 9.75 kHz B) 33.9 kHz C) 7.45 kHz D) 3.41 kHz
17)
18) For a Wien-bridge oscillator, in order to produce proper oscilation, the attenuation ratio of Vout to Vin must be A) 2 to 1 B) 1 to 2 C) 1 to 3 D) 3 to 1
18)
19) The closed-loop voltage gain of the Wien-bridge oscillator must be A) unity B) 3 C) slightly less than unity D) slightly greater than unity
19)
20) This type of oscillator returns a portion of the output signal back to the input with no net phase shift A) square wave generator B) sine wave generator C) triangle wave generator D) feedback oscillator
20)
21) Regarding twin-t oscillators A) both twin-t filters have a high-pass response B) both twin-t filters have a low-pass response C) one filter has a high pass and the other a low-pass response D) any of the above configurations can be twin-t oscillators
21)
22) Oscillators cannot produce A) square waves C) sine waves
22)
B) non-periodic pulse waveforms D) triangle waves 2
23) For initial start-up A) loop gain must be unity B) loop gain must be greater than one C) loop gain must be less than one D) any of the above conditions can start up an oscillator due to a startup spike
23)
24) For oscillation to begin A) gain must be less than one B) gain must be slightly greater than one C) gain must be exactly unity D) gain must be less than one and then continue to decrease
24)
25) A square wave oscillator A) is a type of relaxation oscillator B) has two feedback circuits C) is based on the principle of charging and discharging a capacitor D) all of the above
25)
26) A function generator is used to produce A) sine waveforms C) square waveforms
26)
B) triangle waveforms D) all of the above
27) The resistors and capacitors in the lead/lag network of a Wien-bridge oscillator equal 8.6 k and 0.022 µF. The output frequency must be A) 27.3 kHz B) 2733 Hz C) 841 Hz D) 8.41 kHz
27)
28) Feedback oscillation is based on what principle? A) positive feedback C) negative feedback
28)
B) analog to digital conversion D) ac to dc conversion
29) The high and low pass filters in a twin-T oscillator act as a A) negative feedback path B) phase shift filter C) bandpass filter D) notch filter
29)
30) This category of oscillators use an RC timing network and a device that changes states to generate a periodic waveform A) twin-t B) wein-bridge C) inverting op-amp oscillator D) relaxation oscillator
30)
31) The 555 timer integrated circuit A) only works in astable operation C) has limited use
31)
B) cannot produce a sine wave output D) cannot be used as a VCO
32) A sawtooth generator produces A) a form of sine waveform C) a digital pulse train
B) a variable frequency output D) a type of triangle waveform
33) The output frequency of a 555 timer is A) is always constant C) varies directly with the control voltage
B) varies inversely with the control voltage D) always has a duty cycle of less than 50% 3
32)
33)
34) The most stable LC feedback oscillator is the A) Armstrong C) Colpitts
B) crystal-controlled D) Clapp
4
34)
Answer Key Testname: CHAPTER 10 1) B 2) D 3) D 4) C 5) D 6) B 7) B 8) B 9) A 10) B 11) C 12) D 13) C 14) D 15) D 16) C 17) B 18) C 19) B 20) D 21) C 22) B 23) B 24) B 25) D 26) D 27) C 28) A 29) D 30) D 31) B 32) D 33) B 34) B
5
Chapter 11 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The output of a 7912 regulator is A) -1.2 volt B) +12 volt
C) +1.2 volt
D) -12 volt
1)
2) A shunt regulator differs from a series regulator A) the transistor dissipates much more power B) the transistor is in parallel with the load C) in its ability to maintain constant voltage effectively D) the transistor is a pnp
2)
3) The term tempco refers to a device's A) temporary or intial state C) polarity
3)
B) temperature coefficient D) initial accuracy
4) What term describes how much change occurs in the output voltage over a certain range of load resistance values? A) line regulation B) supply regulation C) load regulation D) voltage regulation
4)
5) What is the purpose of the input capacitor on an IC regulator? A) line filtering B) increased current capacity C) provide better frequency response D) none of the above
5)
6) The input voltage of a 78XX series regulator must be A) at least 3 volts more than the output B) the same as the output C) does not matter what the input voltage is D) at least 2 volts more than the output
6)
7) How much output current is a 78XX series regulator capable of? A) up to 100mA B) up to 1 amp C) up to 100mA only if adequate heat sinking is provided D) up to 5 amps
7)
8) A switching regulator can be a(n) A) step-up regulator C) inverting regulator
8)
B) step-down regulator D) all of the above
9) A series regulator with short-circuit protection protects what component? A) the zener diode B) the voltage divider resistors C) the series-pass transistor D) all of the above components
9)
10) The series resistor in a shunt regulator acts as a voltage divider with what other component? A) the zener B) the control element Q1 C) the error detector D) the sample circuit
10)
1
11) The following component compares the sample voltage with a reference voltage and causes the control element to maintain a constant output voltage A) control element B) reference voltage C) sample circuit D) error detector
11)
12) What happens when the input voltage decreases in a shunt regulator? A) the voltage across the control element transistor increases B) the reference voltage decreases C) the op amp output decreases D) all of the above
12)
13) Which of the following best describes a voltage regulator? A) provides a constant voltage load voltage independent of the load and input voltage B) a constant voltage source with less than 3 percent regulation C) an adjustable constant voltage and current source D) provides a constant voltage and current source independent from the load
13)
14) The output voltage of a step-up regulator is A) never more than twice the input votlage B) equal to the sum of the capacitor voltage and the inductor voltage C) both a and b D) step-up regulators step up current only
14)
15) In order for a voltage regulator to compensate for changing load resistance A) the load current must change B) the output voltage must change too C) both a and b D) none of the above
15)
16) The last two digits of the part number on a 78XX series IC regulator indicates A) power dissipation B) internal resistance C) output polarity D) output voltage
16)
17) Fold-back current limiting is A) used to maintain low current levels B) used to keep the series pass transistor biased C) used primarily in low-power applications D) used primarily in high-current applications
17)
18) Switching regulators are more efficient than linear regulators primarily due to A) the control transistors don't conduct all the time B) capacitive coupling C) advanced processor control efficiency D) fewer current-conducting components
18)
19) The on-off time of a switching regualtor is controlled by A) an RC circuit B) an RL circuit C) a control transistor D) feedback
19)
20) If you want to have a more accurate voltage regulator you would replace the zener diode with A) back-to-back regulators B) a voltage-controlled FET C) a voltage reference IC D) a precision voltage divider
20)
2
21) The LM337 is A) can be used in any of the above configurations B) a variable positive-voltage regulator C) a fixed negative-voltage regulator D) a variable negative-voltage regulator
21)
22) Which type of regulator produces an output voltage that is opposite in polarity from the input? A) step-down B) inverting C) step-up D) cross-over regulator
22)
23) The input voltage to a regulator drops by 7 V and the output voltage changes by 800 mV. The percent line regulation is A) 11.4% B) 89.4% C) 1.13% D) 88.7%
23)
24) Zener diodes have a few drawbacks as reference source voltages A) sensitive to temperature changes B) tendency to be noisy C) Voltage may change slightly with age D) all of the above
24)
25) Which of the following is a basic component of a series linear regulator? A) control element B) error detector and sample circuit C) reference element D) all of the above
25)
26) The ratio of the change of output voltage to a corresponding change of input voltage, expressed as a percentage, is called A) line regulation B) input regulation C) load regulation D) voltage regulation
26)
27) The power switch (transistor) in a switching power supply is turned off and on by A) an RC charge/discharge circuit B) an error detection circuit C) a variable pulse-width oscillator D) a compartor with feedback
27)
28) Maximum load current in a series regulator with over-voltage protection limiting is calculated using A) the op amp's output impedance and the load B) the emitter-base voltage and series resistance C) the voltage drop across the sensing resistors D) none of the above
28)
29) The voltage between the output terminal of an LM317 and the adjust terminal is A) always 2 V B) determined by the voltage divider and the adjust current C) always 1.25 V D) determined by the voltage divider
29)
3
Answer Key Testname: CHAPTER 11 1) D 2) B 3) B 4) C 5) A 6) D 7) B 8) D 9) C 10) A 11) D 12) D 13) A 14) B 15) A 16) D 17) D 18) A 19) D 20) C 21) D 22) B 23) A 24) D 25) D 26) A 27) C 28) B 29) C
4
Chapter 12 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The electrodes from an ECG medical device are generally connected to what electronic component? A) an isolation amplifier B) an OTA C) a low-pass filter D) an isolated power supply
1)
2) A problem with the basic op-amp instrumentation amplifier is A) large power consumption B) comparatively low input impedance C) high common-mode gain requires precisely matched resistors D) low CMRR noise reduction
2)
3) This type of special purpose amplifier is used in high voltage and medical applications A) instrumentation amplifier B) transconductance amplifier C) isolation amplifier D) logarithmic amplifier
3)
4) The Burr-Brown 3656KG is a A) instrumentation amplifier IC C) capacitor coupled isolation amplifier
4)
B) inductor coupled isolation amplifier D) an OTA
5) The voltage gain for the 3656KG iis adjusted using external resistors for A) the output gain only B) both input and output gains are independently adjusted C) the input gain only D) input and output can be adjusted but only to the same level
5)
6) Which best describes the reason logarithmic signal compression is more accurate than linear signal compression? A) logarithmic amplifiers deal with large and small signals equally B) in logarithmic compression, higher voltages are reduced more than small voltages C) phase shift affects linear amplifiers more than logarithmic amplifiers D) linear compression cannot replicate extremely small signals
6)
7) Isolation amplifiers use what type of coupling? A) inductive B) capacitive
7)
C) optical
D) all of the above
8) This amplifier is constructed from three op amps and seven resistors A) Instrumentation amplifier B) Schmitt trigger C) OTA amplifier D) Isolation amplifier
8)
9) Among the uses for operational transconductance amplifiers include A) frequency modulators B) frequency detectors C) amplitude modulators D) both a and b
9)
1
10) The last stage of a multiplier circuit is usually a(n) A) summing amplifier C) OTA amplifiers
B) log amplifier D) antilog amplifier
10)
11) This type of amplifier can be viewed as a voltage to current amplifier A) isolation amplifier B) logarithmic amplifier C) instrumentation amplifier D) transconductance amplifier
11)
12) The transconductance of an OTA is proportional to A) the voltage gain and the bias current C) a constant and the bias current
B) a constant and the voltage gain D) both a and c
12)
13) As OTA bias current increases A) output resistance decreases C) input resistance decreases
B) input resistance increases D) both a and c
13)
14) The input section of an isolation amplifier is comprised of A) an op-amp, a demodulator and an oscillator B) an op-amp, a modulator and an oscillator C) an OTA, a modulator and an oscillator D) an op-amp, a modulator and a PWM
14)
15) The log of 1000 A) 100 C) 2
15)
B) 3 D) none of the above
16) Which of the following is not a benefit of isolation amplifiers? A) separate input and output power supplies B) simple circuit design C) separate input and output grounds D) none of the above
16)
17) An amplifier often used to compress analog data is the A) logarithmic amplifier B) transconductance amplifier C) instrumentation amplifier D) isolation amplifier
17)
18) A special purpose amplifier used in high noise environments is the A) logarithmic amplifier B) transconductance amplifier C) isolation amplifier D) instrumentation amplifier
18)
19) As the gain of an instrumentation amplifier increases A) the bandwidth decreases B) the bandwidth increases C) it becomes more susceptible to noise D) it becomes less linear
19)
20) If the value of the external resistor R G increases, the gain of an instrumentation amplifier
20)
A) increases C) does not change
B) decreases D) both a and c
2
21) In order to make a logarithmic amplifier A) tie the inverting and non-inverting inputs together with a resistor B) replace the feedback resistor with a diode C) replace the feedback resistor with a capacitor D) tie the inverting and non-inverting inputs together with a diode
21)
22) Transconductance amplifier output current is proportional to A) gain time input voltage B) bias voltage C) bias current D) input voltage
22)
23) Isolation amplifiers are often used A) to protect in-hospital communication equipment B) isolate X-ray signals from communication equipment C) to monitor hospital public address signals D) to isolate 60Hz skin common-mode noise from heart signals
23)
24) Where would you install a BJT in an antilog amplifier? A) as a ground shunt B) in series with the input C) in the feedback loop D) as a gain control device between inputs
24)
25) The output op-amp in an isolation amplfiier is a(n) A) non-inverting amplfier C) voltage follower
25)
B) differential amplifier D) inverting amplifier
26) The feedback resistors in aninstrumentation amplfier are both 20 k . If you want a gain of 400 the value of RG must be
26)
27) The voltage followers at the input to an instrumentation amplifier provide A) extremely high input impedance B) high voltage gain C) noise rejection from line signal sources D) all of the above
27)
28) Comparing a linear and a logarithmic plot of diode current and voltage, one thing you will notice is that A) a logarithmic plot will have some curvature B) a linear plot will have some curvature C) a logarithmic plot tends to be more accurate D) none of the above
28)
29) What is the most common form of couplling for solation amplifiers? A) optical B) direct C) transformer
29)
A) 50
B) 200
C) 1 k
30) What is the fundamental property that makes logarithmic amplifiers possible? A) Inductive reactance B) RC time constants C) the characteristics of a pn junction D) none of the above
3
D) 100
D) capacitive
30)
Answer Key Testname: CHAPTER 12 1) A 2) C 3) C 4) D 5) B 6) B 7) D 8) A 9) C 10) D 11) D 12) C 13) D 14) B 15) B 16) B 17) A 18) D 19) A 20) B 21) B 22) A 23) D 24) B 25) B 26) D 27) A 28) B 29) C 30) C
4
Exam
Chapter 13
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What is the purpose of a PLL? A) regulate voltage in audio amplifiers B) synchronize a VCO with an incoming signal C) modulate or demodulate an incoming signal D) stabilize IF gain
1)
2) A fiber-optic cable has values of n1 = 1.40 and n2 = 1.35. Solve for the critical angle. A) 0.99 degrees B) 40.9 degrees C) 42.4 degrees D) 15.4 degrees
2)
3) Baud rate refers to A) binary on or off condition B) binary bits transmitted or received per second C) digital pulse signals D) none of the above
3)
4) What is the reason 300-baud rate digital data in its pure form can't be transmitted over the phone lines? A) 300 baud translates to 300 Hz which is outside the phone system bandwidth B) phone systems only transmit voice data C) 300 baud translates to 150 Hz which is outside the phone system bandwidth D) none of the above
4)
5) Fiber -optic systems are superior to copper systems as they A) are faster B) have greater capacity C) are less susceptible to RFI and EMI D) all of the above
5)
6) Which of the following do not belong in a block diagram of an AM superheterodyne receiver? A) limiter B) detector C) mixer D) audio amplifier
6)
7) The maximum number of input polarity combinations that a linear mulitplier cn accept is A) 16 B) 2 C) 4 D) 256
7)
8) AM broadcast receivers' frequency band is 540KHz to 1640KHz. Which of the following is a carrier in that band? A) no way to find carrier with the provided information B) all AM carriers are 455 kHz C) any frequency below 540KHz or above 1640KHz D) 950 KHz
8)
9) Automatic gain control provides a dc level of output A) of a fixed value B) that is compressed C) that is proportional to the strength of the input D) many times greater than the input
9)
1
10) A frequency spectrum is A) a graphical representation of the frequency content of a signal B) frequencies represented as linear quantities C) a graphical representation of the output voltage of a multiplier D) none of the above 11) Which component or system can be shared in a typical AM/FM receiver? A) discriminator B) audio amplifier C) mixer 12) In linear multipliers, SF stands for A) side-band frequency C) single-ended frequency
10)
D) RFamplifier
11)
12)
B) standard frequency D) scale factor
13) A communications system can be classified as A) any live transmission of data B) a system that sends information from one point to another C) any form of media D) a transmitter and receiver
13)
14) In suppressed carrier modulaton, a linear multiplier would be used in which circuit? A) detector B) local oscillator C) mixer D) IF amplifier
14)
15) What is the IF in a standard AM radio? A) 660Hz B) 449Hz
15)
C) 60Hz
D) 455KHz
16) Iif the X2 and Y2 inputs to a linear multiplier are grounded A) it is used in an AM modulator B) t is being used in single-ended mode C) it is being used in differential mode D) there is no output
16)
17) The X and Y inputs to an AD532 are connected A) either differential or single-ended C) as inverted amplifiers
17)
B) as single-ended inputs D) in differential mode
18) Balanced modulation implies A) the sidebands are the inverse of each other B) the output will be sum and difference signals plus the carrier C) the carrier signal is balanced out D) both sidebands are balanced
18)
19) An AD532 has the following inputs: (X1 - X2)(Y1 - Y2) = 15.6 V2 . This means the output voltage will be A) 1.56 V B) 15.6 V C) 1.56 V2 D) 24.3 V
19)
20) The input to an AD532 linear multiplier can be viewed as A) an AM mixer B) a balanced modulator C) a voltage follower D) two op-amps
20)
2
21) Modems have two modes of operation A) FSK and DTE C) Originate and answer
21)
B) Command and control D) timing and control
22) Which of the following in not a mode of light propagation? A) single-mode step index B) multimode graded index C) single-mode graded index D) multimode step index
22)
23) In addition to math operations, linear multipliers can be used for A) phase detectors B) DTE's C) modems
23)
D) DCE's
24) Full duplexing is achieved A) by assigning different parity values to the transmit and receive data B) by assigning transmitting and receiving data different bandwidths C) by using different conductors for each D) by employing TDM
24)
25) A DCE whose basic function is to modulate and demodulate is called a A) modem B) digital terminal equipment C) bandwidth expander D) frequency shift keyer
25)
26) In a fiber optic system, if the angle of incidence is greater than the critical angle A) absorption occurs B) total reflection occurs C) scattering increases D) scattering decreases
26)
27) If a 1 MHz carrier is amplitude modulated with a 7 KHz signal what are the frequency components (upper and lower side bands)? A) 1.07 MHz and 1.7 MHz B) 14 KHz and 28 KHz C) 1.007 MHz and 993 KHz D) 140 KHz and 280 KHz
27)
28) When two frequencies are mixed to produce sum and difference frequencies, the process is called A) mixing B) sequencing C) heterodyning D) oscillator mixing
28)
29) The range of frequencies between 200 Hz and 20 KHz is A) the lowest end of the radio frequency spectrum B) the audio range C) demodulated FM D) demodulated AM
29)
30) FM broadcast bands consist of carrier frequencies within what range? A) 88 MHz and 108 MHz B) 88 KHz and 108 MHz C) 88 KHz and 108 KHz D) none of the above
30)
31) The discriminator in an FM system is roughly the same as what component in an AM system? A) IF amplifier B) limiter C) detector D) de-emphasis network
31)
3
Answer Key Testname: CHAPTER 13 1) B 2) D 3) B 4) C 5) D 6) A 7) C 8) D 9) C 10) A 11) B 12) D 13) B 14) C 15) D 16) B 17) A 18) C 19) A 20) D 21) C 22) C 23) A 24) B 25) A 26) B 27) C 28) C 29) B 30) A 31) C
4
Chapter 14 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Most integrated circuit analog switches utilize what type of circuitry? A) MOSFET B) BJT C) solenoid
D) JFET
1)
2) 10 volts can be represented by how many discreet levels by 4-bits? A) infinite levels B) four levels C) sixteen levels including zero D) fifteen levels including zero
2)
3) A basic frequency to voltage converter A) utilizes an integrator C) has a comparator in the circuit
3)
B) uses a one-shot D) all of the above
4) The basic process of controlling room temperature is accomplished in what order? A) analog temperature to digital process to analog control B) analog temperature to digital process to digital control C) digital temperature to digital process to digital control D) either a or b is a possibility
4)
5) The time required for a sample and hold amplifier to sample its final value when the control voltage switches from its hold level to its sample level is called A) droop B) acquisition time C) feedthrough time D) aperture time
5)
6) A single-slope converter A) employs a counter and latach output C) uses a ramp generator instead of a DAC
6)
B) uses a comparator at the input D) all of the above
7) A DAC that does not miss any steps when sequenced over its entire range is A) fully accurate B) an R/2R DAC C) monotonic D) a stair-step ramp DAC
7)
8) This quantity can be defined as having a continuous value over time A) variable B) continuous C) analog
8)
D) digital
9) The change in the sample voltage over the hold interval is called A) attenuation B) insertion loss C) drop-out voltage D) droop
9)
10) The ADG 1213 analog switch has two NO swithces and two NC switches. This makes by tying the inputs of the two pairs together it can be used for A) a NOR gate B) a simple DAC C) multiplexing D) a simple ADC
10)
11) What describes the number of steps, compartments or individual units a sample is divided by in order to yield a digital output? A) monotonicity B) linearity C) resolution D) accuracy
11)
1
12) In a four-bit binary weighted DAC, if the 2 3 resistor is 2 k then the 2 1 reistor must be A) 8 k B) 4 k C) 1 k D) 6 k
12)
13) What type of amplifier tracks the input voltage during the sample interval? A) sample and hold B) tracking-sample amplifier C) sample/track-and-hold D) none of the above
13)
14) What determines the resolution of an analog to digital converter? A) the number of bits B) the input voltage C) baud rate D) input frequency
14)
15) This type of A/D converter uses a DAC and binary counter to generate a digital value of an analog input A) encoder B) stairstep-ramp C) sampler D) flash converter
15)
16) An inverting adder can be used as a digital to analog converter. The critical component in this case would be A) the input resistor tolerance B) the rise time of the op-amp C) the feedback resistor D) the supply voltages
16)
17) The most widely used analog to digital conversion method is A) successive-approximation B) dual-slope C) single-slope D) tracking
17)
18) In accordance with the Nyquist sampling theory what sample rate must a 200Hz waveform be sampled at? A) more than 400Hz B) more than 3200Hz C) more than 800Hz D) more than 1600Hz
18)
19) A voltage to frequency converter A) increases output frequency as input voltage increases B) frequency and input voltage are not interdependent C) decreases output frequency as input voltage increases D) must have a clock input signal
19)
20) The comparison of the expected output to the actual DAC output is called A) monotonicity B) linearity C) accuracy
D) resolution
20)
21) This type of analog to digital converter uses a series of comparators at the input A) sampler B) flash method C) reference converter D) encoder
21)
22) A double pole-double throw analog switch has how many inputs and outputs? A) two inputs-two outputs B) one input-one output C) one input-two outputs D) two inputs-one output
22)
2
23) What term represents the amount of time it takes for an analog signal to be converted into binary data? A) resolution rate B) quantization time C) sample time D) conversion time
23)
24) One benefit to digital sampling of analog data is A) the sample waveform can be easily stored B) the levels between the sampled points on the waveform can be easily found C) the sample will reproduce an exact replica of the input D) none of the above
24)
25) Which of the following is not an A/D conversion error? A) missing code B) offset C) drop-out voltage D) incorrect code
25)
26) An analog multiplexer allows analog data from multiple sources to share the same transmission line. How is this achieved? A) all input data has individual voltage values B) each data input will conduct at different time intervals C) all data has to have different bandwidths D) none of the above
26)
27) What type of component actually stores the acquired data in a simple sample and hold circuit? A) shift register B) capacitor C) resistor D) flip-flop
27)
28) What is the fastest method of analog to digital conversion? A) converter method B) flash or simultaneous C) R/2 ladder D) proportional sampling
28)
29) A sample and hold circuit that is operating with a very short sample time should use a(n) A) window comparator B) invering amplifier C) small value capacitor D) large value capacitor
29)
30) Which characteristic of the ADC0804 indicates that it can interface with a microprocessor bus system? A) montonocity B) tristate outputs C) eight-bit resolution D) on-chip clock generator
30)
3
Answer Key Testname: CHAPTER 14 1) A 2) C 3) D 4) D 5) B 6) D 7) C 8) C 9) D 10) C 11) C 12) A 13) C 14) A 15) B 16) A 17) A 18) A 19) A 20) C 21) B 22) A 23) D 24) A 25) C 26) B 27) B 28) B 29) C 30) B
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Chapter 15 Exam Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following is not performed by an rms-to-dc converter? A) divide-by-two circuit B) square root circuit C) averaging circuit D) squaring circuit
1)
2) Basic analog physical parameters such as angular position, temperature, pressure, strain and flow rate are measured by what types of devices? A) transmitters B) interpolators C) transducers D) telemeters
2)
3) This quantity is usually measured using a spring-supported seismic mass A) acceleration B) volume C) velocity
3)
D) weight
4) One method of providing an accurate thermocouple interface is A) use a reference voltage in the feedback circuit B) capacitive coupling C) use a swamping resistor D) use a reference thermocouple
4)
5) Which type of circuit uses an rms.-to-dc converter to keep an output constant for varying input signals? A) PLL B) Synthesizer C) window comparator D) Automatic gain control
5)
6) A dummy strain gage is used to A) compensate for thermal expansion C) balance the bridge
6)
B) simulate a strain measurement D) compensate for nonlinearity
7) How does a binary word represent angular position? A) binary is converted to radian measure in octal B) each bit position is weighted as an angular measurement in degrees C) one word divides 180 degrees into 26000 intervals D) any of the above cacn be used
7)
8) One common method of measuring flow rate of a fluid through a pipe is A) the wein-bridge method B) hall effect transducer C) a twin-t flow detector D) the differential pressure method
8)
9) The primary difference between resolvers and synchros is A) the angle between the rotor windings B) the angle between the stator windings C) the induced voltage in the stator D) none of the above
9)
10) The ac value that is equal to the same dc heating effect is usually called A) rms value B) heat-equivalent value C) peak value D) half-cycle average value
10)
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11) What affects the accurate operation of a resistance bridge measuring temperature? A) RTD lead capacitance B) RTD lead resistance C) ambient temperature differential D) RTD lead inductance
11)
12) How does using a low-pass filter (single-pole) on the input of a voltage follower makes it an averager? A) the RC filter is designed to do mathematical averaging B) the first time constant of the capacitor is about 63% or average value of the input C) the RC filter will pass only the dc component (average value) D) none of the above
12)
13) These types of circuits are used to interfact thermocouples to various types of electronic systems. A) thermocouples adpaters B) signal conditioners C) interfacers D) compensators
13)
14) The deformation of a material due to a force acting on it is called A) distortion B) pressure C) strain
14)
D) stress
15) This device has the same function as a thermocouple but has a more linear output A) LTC B) LTD C) ATD D) RTD
15)
16) Thermistors A) are very nonlinear C) can have both NTC and PTC
16)
B) have high sensitivity D) all of the above
17) When heat travels up a thermocouple lead and is disspated in the atmosphere, this is referred to as A) ambient loss B) themal shunting C) thermal differential leakage D) all of the above
17)
18) This quantity indicates a change in position of a body or point A) displacement B) motion coefficient C) relative velocity D) FIFO
18)
19) This device is often used as an electronic switch in many applications A) SCR B) SPDT C) back-to-back diode D) SPST
19)
20) Which of the following is not a force-related parameter? A) strain B) motion C) mass
D) pressure
20)
21) Thermistors have A) positive temperature coefficients B) the temperature coefficient is a function of polarity C) negative temperature coefficients D) either a or b
21)
22) A device that exhibits a change in resistance based on a change in pressure is called a A) psi gage B) pressure transducer C) gage transducer D) none of the above
22)
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23) In order to find the square of a voltage value A) use an op-amp with a linear multiplier in the feedback loop B) use cascaded voltage followers C) use a linear multiplier with two inputs tied together D) any of the above will yield the same result 24) This device is formed by adjoining two dissimilar metals A) RTD B) thermocouple C) sequencer
23)
D) thermistor
24)
25) The crest factor of a waveform is A) the value of the highest induced voltage spike B) the ratio of its peak value to its rms value C) the ratio of its rms value to its peak value D) the value of the highest induced current spike
25)
26) A cold-junction A) its value depends on ambient temperature B) forms an unwanted thermocouple C) can have an unpredictable effect on the thermocouple voltage D) all of the above
26)
27) SDCs and RDCs both operate internally with resolver format voltage. This means that synchro output voltagesmust be formatted. What device accomplishes this? A) scott-t transformer B) resolver formatter C) synchro formatter D) ADC converter
27)
28) This type of transducer is used for shaft angle measurement A) anemometer B) synchro C) digitizer
D) tachometer
28)
29) Which of the following is not a temperature sensor? A) dynamometer B) RTD
C) thermistor
D) thermocouple
30) A 3-wire bridge is used to A) compensate for a cold junction C) compensate for wire resistance
B) add a reference thermocouple D) add a reference RTD
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29)
30)
Answer Key Testname: CHAPTER 15 1) A 2) C 3) A 4) D 5) D 6) A 7) B 8) D 9) B 10) A 11) B 12) C 13) B 14) C 15) D 16) D 17) B 18) A 19) A 20) C 21) D 22) B 23) C 24) B 25) B 26) D 27) A 28) B 29) A 30) C
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