智慧樹知到《模擬電子技術基礎（西安郵電大學版）》章節(jié)測試【完整答案】

1、最新資料歡迎閱讀 智慧樹知到模擬電子技術基礎（西安郵電大學版）章節(jié)測試【完整答案】 智慧樹知到模擬電子技術基礎(西安郵電大學版)章節(jié)測試答案 第一章 1、Which of the following is not a commonly used semiconductor material”? ( ) A:carbon B:lead C:silicon D:germanium 答案: lead 2、The characteristic of an ideal diode are those of a switch that can conduct current( ) . A:in both

2、directions B:in one direction only C:in both directions but in only one direction at a time D:depends on the circuit it is used in 答案: in one direction only 3、When a diode is doped with either a pentavalent or a trivalent impurity its resistance will ( ) . A:increase B:decrease C:make the resistance

3、 stable against variation due to temperature 答案: decrease 4、The piecewise linear model, equivalent circuit of the diode consists of ( ). A:a junction capacitor, a battery, a small resistor, and the ideal diode B:a battery, a small resistor, and the ideal diode C:a battery and the ideal diode D:the i

4、deal diode 答案: a battery, a small resistor, and the ideal diode 5、When a p-n junction is reverse-biased, its junction resistance is ( ). A:high B:low C:determined by the components that are external to the device D:constantly changing 答案: high 第二章 1、What is the value of the voltage dropped across fo

5、rward-biased silicon diodes that are connected in parallel with each other? ( ). A:11.3 V B:35 V C:7 V D:4 V 答案: 7 V 2、The resistor voltage and resistor current in this circuit are ( ).image.png A:10 V, 5 mA B:11 V, 2 mA C:11 V, 11 mA D:2 V, 11 mA 答案: 11 V, 11 mA 3、Which of the following circuits is

6、 used to eliminate a portion of a signal? ( ). A:Clipper B:Damper C:Voltage multiplier D:Voltage divider 答案: Clipper 4、The circuit shown here is a ( ). image.png A:series clipper B:parallel clipper C:series clamper D:shunt clamper 答案: parallel clipper 5、The Zener diode must be operated such that ( )

7、. A:image.png B:image.png is less than the specified image.png C:the applied voltage is greater than image.png D:All of these 答案: All of these 第三章 1、In the active region, the base-emitter junction ( ). A:and the base-collector junctions are both forward-biased B:and the base-collector junctions are

8、both reverse-biased C:is forward-biased while the base-collector junction is reversed-biased D:is reverse-biased while the base-collector junction is forward-biased 答案: C 2、A BJT has measured dc current values of image.png = 0.1 mA and image.png= 8.0 mA. When IB is varied by 100 μA, IC changes by

9、 10 mA. What is the value of the βac for this device?( ). A:80 B:10 C:100 D:800 答案: C 3、When a BJT is operating in the active region, the voltage drop from the base to the emitter image.png is approximately equal to the ( )。 A:base bias voltage B:base current times the base resistor C:diode dro

10、p (about 0.7 V) D:emitter voltage 答案: C 4、BJTs are commonly used as ( ). A:the primary components in amplifiers B:series damper circuits C:the primary components in rectifiers 答案: A 5、The condition where increase in bias current will not cause further increases in collector current is called ( ). A:

11、cutoff B:saturation C:active operation 答案: B 第四章 1、When a BJT is biased in the cutoff region the collector-to-emitter voltage is typically equal to ( ). A:the emitter voltage B:03 V C:the collector current times the collector resistor D:the collector supply voltage 答案: D 2、Calculate the collector-em

12、itter voltage for this emitter-stabilized circuit.( ) image.png A:32 V B:10.68 V C:1335 V D:14.24 V 答案: 4.32 V 3、The difference between the resulting equations for a network in which an npn transistor has been replaced by a pnp transistor is ( ). A:the values of the resistors B:the value of β C

13、:the sign associates with the particular quantities 答案: C 4、The term quiescent means ( ). A:midpoint-biased B:at rest C:active D:inactive 答案: D 5、Voltage-divider bias stability is ( ). A:dependent on alpha B:dependent of beta C:dependent on the collector resistor D:independent of beta 答案: D 第五章 1、Gi

14、ven this configuration, determine the input impedance if VS = 40 mV, Rsense = 0.5 kΩ, and the input current is 20 μA.( )image.png A:5 MΩ B:822 MΩ C:1,500 Ω D:582 kΩ 答案: C 2、The image.png transistor model replaces the ( ) with the junction diode”s ac resistance. A:col

15、lector-base junction B:collector-emitter junction C:emitter-base junction 答案: C 3、Calculate the voltage gain for this circuit. ( )image.png A:-137.25 B:-8.4 C: -7.91 D:-16.34 答案: A 4、A transistor amplifier has an input signal applied to its emitter terminal and an output signal taken from its collec

16、tor terminal. The amplifier is a(n) ( ). A:common-emitter amplifier B:common-base amplifier C:common-collector amplifier D:emitter follower 答案: B 5、The voltage gain of a very well-designed common collector amplifier configuration, using a pnp transistor, is ( ). A:about -0.9 B:about 0.9 C:in the ran

17、ge 0.95 to 0.99 D:in the range -0.95 to -0.99 答案: C 第六章 1、Shockley”s equation defines the ( ) of the FET and are unaffected by the network in which the device is employed. A:image.png characteristics B:drain characteristics C:input/output characteristics D:transfer characteristics 答案: D 2、For an n-c

18、hannel depletion MOSFET, image.png= 8 mA and image.png = -6 V. If image.png= 0.8 V, what is the value of the drain current, image.png? ( ) A:8 mA B:10.25 μA C:10.28 mA D:6 mA 答案: C 3、The region of the JFET drain curve that lies between pinch-off and breakdown is called ( ). A:the constant-voltage

19、 region B:the ohmic region C:the saturation region 答案: C 4、In the family of FETs, you can expect to find ( ). A:an n-channel type B:a p-channel type C:unipolar structure 答案: ABC 5、FETs usually ( ). A:are less sensitive to temperature change than BJTs B:have a higher input impudence than BJTs C:are s

20、maller in construction than BJTs 答案: ABC 第七章 1、This graphical solution represents ( ).image.png A:fixed bias for an n-channel JFET B:voltage-divider bias for an n-channel JFET C:self bias for an n-channel JFET 答案: C 2、Generally, it is good design practice for linear amplifiers to have operating poin

21、ts that close to ( ). A:are close to saturation level B:the cut-off region C:the midpoint of the load line 答案: C 3、Which of the following biasing circuits can be used with E-MOSFETs? ( ) A:self bias B:zero bias C:drain-feedback bias D:current-source bias 答案: C 4、The primary difference between JFETs

22、and depletion-type MOSFETs is ( ). A:JFETs can have positive values of image.png and levels of drain current that exceed image.png B:depletion-type MOSFETs can have positive values of image.png and levels of image.png that exceed image.png C:depletion-type MOSFETs can have only positive of image.png

23、 D:JFETs can have only positive values of image.png 答案: B 5、A JFET can be biased in several different ways. The common method(s) of biasing an n-channel JFET is(are) ( ). A:self-bias configuration B:voltage-divider bias configuration C:fixed-bias configuration 答案: ABC 第八章 1、The FET version of the BJ

24、T”s common-emitter configuration is the ( ) circuit. A:common-source B:common-gate C:common-drain D:common-current 答案: A 2、Calculate the input impedance for this FET amplifier. ( )image.png A:image.png B:image.png C:image.png D:image.png = would depend on the drain current image.png 答案: 3、Design thi

25、s circuit for a voltage gain of 10. You have to calculate the value of resistor image.png and image.png. It is desired that the transistor operate with a relatively high value of image.png. For this device, a high value of image.png is defined as image.png. ( )image.png A:image.png B:image.png C:ima

26、ge.png D:image.png 答案: 4、The ( ) amplifier has high input impedance, low output impedance, and low voltage gain. A:common-gate B:common-drain C:common-source 答案: B 5、The ( ) FET amplifier has low input impedance, high output impedance, and high voltage gain. A:common-gate B:common-drain C:common-sou

27、rce 答案: A 第九章 1、Calculate the low frequency break point due to the capacitor image.png for this BJT amplifier. ( )image.png A:image.png B:image.png C:image.png D:image.png 答案: 2、If several identical stages of amplifiers, each having the exact same upper and lower cutoff frequencies, are connected in

28、 cascade, then the bandwidth of the resulting amplifier will ( ). A:increase B:remain unchanged C:decrease D:be equal to the sum of all the individual bandwidths 答案: C 3、A 3-dB drop in β occurs at ( ). A:image.png B:image.png C:image.png D:image.png 答案: 4、Negative dB values represent ( ). A:pow

29、er gain B:power losses C:power values that do not change 答案: B 5、An amplifier has a midband power gain of 24,500. What is the value of the power gain in dB for the circuit? ( ) A:87.78 dB B:43.9 dB C:39 dB 答案: B 第十章 1、Under difference-mode operation, the difference-mode voltage gain for this circuit

30、 is ( ).image.png A:0397 B:80 C:40 D:08 答案: C 2、The operational amplifier will only slightly amplify signals ( ). A:when the supply voltages are more then ±25 V B:when the supply voltages are less then ±5 V C:that are common on both the inputs D:that are different on both the inputs 答案

31、:C 3、The inverting and noninverting inputs to an op-amp are used to drive a(n) ( ) amplifier. A:inverting B:noninverting C:differential D:open-loop 答案: C 4、When a given op-amp has a common-mode input of 10 V, the output of the device is 10 V. When the device has a differential input of 2 mV, the out

32、put of the device is 10 V. What is the CMPR of the device? ( ) A:5 : 1 B:5000 : 1 C:1000 : 1 D:5,000,000 : 1 答案: B 5、The bandwidth of an amplifier is ( ). A:the range of frequencies over which gain remains relatively constant B:the range of frequencies between the lower and upper 3 dB frequencies C:

33、 the range of frequencies found using image.png 答案: ABC 第十一章 1、 If the input voltage is 0.25 V and the output is -2.5 V, the value ofimage.png must be ( ).image.png A:40.0 kΩ B:20.0 kΩ C:16.0 kΩ D:0 kΩ 答案: B 2、The output voltage, VO, is given by ( ).image.png A:image.png B:im

34、age.png C:image.png 答案: 3、A summing integrator is an op-amp integrator that has ( ). A:multiple feedback capacitors B:multiple input resistors C:multiple input resistors and feedback capacitors 答案: C 4、A second order low-pass filter has a high-end roll-off of ( ). A:60 dB/octave B:40 dB/decade C:20

35、dB/octave D:6 dB/decade 答案: B 5、An active filter that provides a constant output for input signals above image.png is called an ideal ( ). A:low-pass filter B:high-pass filter C:bandpass filter 答案: B 第十二章 1、A class B amplifier (not push-pull) ( ). A:conducts through 360° of the input waveform B:

36、conducts through 180° of the input waveform C:conducts between 180° and 360° degrees of the input waveform, depending on the amount of dc bias D:conducts through less than 180° of the input waveform 答案: B 2、Crossover distortion in class B amplifiers is prevented by ( ). A:biasing the

37、 transistors deeply into cutoff B:biasing the transistors slightly above cutoff C:using complementary-symmetry transistors D:increasing the load resistance 答案: B 3、The maximum theoretical efficiency of an RC-coupled class A amplifier is ( ). A:25% B:50% C:78.5% D:99% 答案: A 4、Power amplifiers are typically used to drive low impedance loads.( ) A:對 B:錯 答案: A 5、The power that an amplifier delivers to a load is equal to the difference between the power that the c