中国大学Analog Electronics Technique章节答案(慕课2023完整答案)
44 min read中国大学Analog Electronics Technique章节答案(慕课2023完整答案)
Test questions for The Ideal Operational Amplifier
1、The大学答案答案 two input terminals of an operational amplifier are labeled as:
A、high and low
B、慕课positive and negative
C、完整inverting and noninverting
D、中国章节differential and nondifferential
2、大学答案答案For the circuit in the Figure,慕课 the output voltage vo is ( ).
A、-6V
B、完整-5V
C、中国章节-1V
D、大学答案答案-0.2V
3、慕课For the circuit in Figure,完整 the current ix is ( )
A、0.6mA
B、中国章节0.5mA
C、大学答案答案0.2mA
D、慕课1/12 mA
4、For the circuit in Figure, current io is( )
A、-10 μA
B、-2.5 μA
C、10/12 μA
D、10/14 μA
5、If vs=8 mV, in the circuit of Figure, the output voltage is( )
A、-44 mV
B、-8 mV
C、4 mV
D、7 mV
6、The power absorbed by the 4k ohm resistor in Figure is( ).
A、9 mW
B、4 mW
C、2 mW
D、1 mW
7、For the circuit in Figure,the output voltage v0 is( ).
A、3 V
B、-3 V
C、-1 V
D、-2 V
8、For the circuit in Figure,the output current io is( ).
A、0.2 mA
B、-0.2 mA
C、0.1 mA
D、-0.1 mA
9、For the circuit in Figure,the output voltage vo is( ).
A、5V
B、-5V
C、3.75V
D、-3.75V
10、For the circuit in Figure,the output voltage vo is ( )
A、5 V
B、-5 V
C、8 V
D、-8 V
11、For the circuit in Figure,the output voltage vo is ( ).
A、5 V
B、-5 V
C、3.8 V
D、-3.8 V
12、Assume the operational amplifiers are ideal,if the input voltage is +1V，Determine vo=( ).
A、1 V
B、-1 V
C、2 V
D、0 V
13、Assume the operational amplifiers are ideal,Determine vo=( );
A、1 V
B、-1 V
C、2 V
D、0 V
14、For the circuit in Figure,the output voltage vo is( )
A、150 mV
B、250 mV
C、350 mV
D、450 mV
15、For the circuit in Figure,the output voltage vo is( )
A、3.2 V
B、-0.8 V
C、2.4 V
D、1.2 V
16、For the circuits shown as Figure, assume the op-amps is ideal, and the maximun output voltage of all of the op-amps is ±13V, when time is t=0s, give the input voltage is a step in voltage, and the amplitude of the input is 100mV, when time is t=1s, determine the output voltage of each op-amp is( ).
A、13 V
B、-13 V
C、0 V
D、100 mV
17、For the circuit in the Figure, the op-amps are ideal, the input resistances of the two circuits are ( )
A、Ri1=Ri2=1k ohm
B、Ri1<Ri2
C、Ri1>Ri2
D、Ri1=Ri2=∞
18、Assume all the Op-Amps are ideal, determine vo in terms of vi is （ ）
A、vo=-0.5(vi+5)
B、vo=0.5(vi+5)
C、vo=2(vi+5)
D、vo=-2(vi+5)
19、Determine the voltage transfer ratio vo/vs in this op-amp circuit, where R=10k ohm.
A、-1/3
B、-2/3
C、1/3
D、2/3
20、Assume all the Op-Amps are ideal, and when time t=0, the capacitor voltage vc=0, then when t=0, vo1=( ), vo2=( ).
A、vo1=4V,vo2=1V;
B、vo1=-4V,vo2=-1V;
C、vo1=7V, vo2=1V;
D、vo1=7V, vo2=-2V
21、Assume all the Op-Amps are ideal, and when time t=0, the capacitor voltage vc=0, then when t=( ? )s, the output voltage vo=0.
A、1
B、1/70
C、1/35
D、2
22、For an ideal op amp, which of the following statements are not true?
A、The differential voltage across the input terminals is zero
B、The current into the input terminals is zero.
C、The current from the output terminal is zero
D、The input resistance is zero
E、The output resistance is zero
23、Difference amplifiers maybe used in ( ).
A、instrumentation amplifiers
B、voltage followers
C、buffers
D、summing amplifiers
E、subtracting amplifiers
24、In the linear operational amplifiers circuit, the inverting input of the operational amplifier is virtual ground.
25、The voltage gain of the voltage follower is 1, so it can be replaced by a wire.
26、In the case of open-loop, the integrated operational amplifier must work in the non-linear region.
27、Assume all the Op-Amps are ideal, determine vo is （ ）V.
Lecture 2 Semiconductor Materials and Diodes Circuits
Test questions for Semiconductor Materials and Diodes Circuits
1、At room temperature, the concentration relationship between free electrons and holes in intrinsic semiconductors is as follows （ ）
A、Undetermined
B、More free electrons
C、More holes
D、Same
2、What are the majority carriers in n-type materials?
A、holes
B、free electrons
C、Positive ions
D、Negative ions
3、What are the minority carriers in p-type materials?
A、holes
B、free electrons
C、Positive ions
D、Negative ions
4、After the formation of PN junction, the relationship between diffusion current and drift current is as follows （ ）
A、More diffusion current
B、More drift current
C、Same
D、Undetermined
5、When PN junction is reverse biased, the resistance becomes （ ）
A、smaller
B、larger
C、Unchanged
D、Undetermined
6、When the PN junction is forward biased , the current is mainly（ ）
A、Reverse drift current
B、Forward diffusion current
C、Forward drift current
D、Reverse diffusion current
7、For the circuit shown in Figure， when Vγ=0.7V， the diode voltage VD and the current ID are （ ）
A、VD=0.7V, ID=1mA
B、VD=0.5V, ID=1mA
C、VD=0.5V, ID=0mA
D、VD=0.7V,ID=0mA
8、When the temperture T increases， the forward voltage of the PN junction ( )
A、Increase
B、Decrease
C、unchanged
D、uncertain
9、The concentration of the majority carriers in the extrinsic semiconductor is mainly affected by ( ).
A、The concentration of impurity
B、The temperature
C、The crystal defect
D、The doping technology
10、The concentration of the minority carriers in the extrinsic semiconductor is mainly affected by ( )
A、The concentration of impurity
B、The temperature
C、The crystal defect
D、The doping technology
11、The zener diode circuit is shown as figure, if VI =10V，R =100ohm，VZ =5V，IZ(min)=5mA，IZ(max)=50mA,T、then the reisitance of RL should be ( )
A、> 111 ohm
B、< 111 ohm
C、> 111 k ohm
D、< 111 k ohm
12、The circuit is shown as figure, and VDD = 2 V，R = 1 kohm,vs=50sin(2pi*50t)mV，and Vγ=0.7V, then the quiescent current of the diode is ( ), the quiescent voltage of the output vO is ( ) , and the ac voltage amplitude of the output is ( ) .
A、2mA，2V；0.05V
B、1.3mA，1.3V；0.05V
C、2mA，2V；0.049V
D、1.3mA，1.3V；0.049V
13、The circuit is shown as figure, the input voltages are shown in the table, the output voltage should be ( )
A、a
B、b
C、c
D、d
14、The circuit is shown as figure,the diodes are silicon diodes, when vs = 6sinwt V, please use the case1 model (Vr=0.7V) to analysis the circuit, the output waveform should be ( )
A、a
B、b
C、c
D、d
15、The circuit is shown as figure , if the RMS value of the ac sine signal is 220V, RL = 0.1k,we use the ideal model to analysis the circuit, then the peak inverse voltage of the diode is ( ).The maximum rectified current of the diode is ( ).
A、220V，0.99A
B、220V，1.98A
C、311V，1.98A
D、311V，0.99A
16、For the circuit shown as figure, if we use ideal model, and the amplitude of the ac sine signal is 24V, then the peak current of the diode is( ), and the peak inverse voltage of the diode is( ）
A、240mA，24V
B、120mA，12V
C、120mA，36V
D、360mA，36V
17、The circuit is shown as figure,the diodes are silicon diodes, and Vr=0.7V, the diodes D1 and D2 should be ( ).
A、D1 on, D2 on;
B、D1 on, D2 off
C、D1 off, D2 off
D、D1 off,D2 on
18、The circuit is shown as figure, the load voltage is VL=9V, aand the input voltage maybe vary between 11 and 13.6V, the current of the load will vary from 0 to 100mA, the the maximum current of the zener diode is ( )
A、100mA
B、200mA
C、300mA
D、400mA
19、In order to form n-type semiconductors, What elements can you add ( )
A、B
B、C
C、Al
D、Si
E、P
F、Ga
G、Ge
H、As
20、In order to form p-type semiconductors, What elements can you add ( )
A、B
B、C
C、Al
D、Si
E、P
F、Ga
G、Ge
H、As
21、For the actual diode, as long as the positive bias voltage is greater than zero, the diode will turn on.
22、When using zener diodes, current limiting resistors are not required.
23、For general diodes, LEDs and photodiodes, forward bias voltage is required for normal operation.
Lecture 3 The Field-Effect Transistor
Test questions for The Field-Effect Transistor
1、For a p-channel Enhancement-Mode MOSFET, to create an inversion layer,we must add what gate to source voltage VGS?
A、Positive
B、Negative
C、Arbitrary
D、Indeterminate
2、The drain current of the MOSFET is formed by the ( ） drift movement ?
A、majority carrier
B、minority carrier
C、two carriers
D、Indeterminate
3、The drain current of the MOSFET is controlled by the （ ）
A、the gate current iG
B、the gate to source voltage VGS
C、the darin to source voltage VDS
D、the gate to drain voltage VGD
4、The drain current versus gate-to-source voltage characteristics is shown in Figure, the FET should be ( ).
A、Enhancement-mode NMOSFET
B、Enhancement-mode PMOSFET
C、Depletion-mode NMOSFET
D、Depletion-mode PMOSFET
5、For the circuits shown in Figure, find which circuit can work as an amplifier ( ).
A、A
B、B
C、C
D、D
6、The drain current versus gate-to-source voltage characteristics is shown in Figure， and for the MOSFET , the voltage of the three terminals are: VS=-5V,VG=1V,VD=3V, the work region of this MOSFET is ( ).
A、cutoff
B、saturation
C、nonsauration
D、Indeterminate
7、The threshold voltage of the MOSFET in the circuit is VTN=1V, not consider the voltage drop of the drain resistor, Determine the work region of the MOSFET in the circuit. （ ）
A、cutoff
B、saturation
C、nonsauration
D、Indeterminate
8、The threshold voltage of the MOSFET in the circuit is VTP=-1V, not consider the voltage drop of the drain resistor, Determine the work region of the MOSFET in the circuit. ( )
A、cutoff
B、saturation
C、nonsauration
D、Indeterminate
9、In the circuit in Figure， VGSQ=（ ）V，ID=（ ）mA，VDS=( )V;
A、VGSQ=1V,IDQ=1mA,VDSQ=3V;
B、VGSQ=2V,IDQ=0.1mA,VDSQ=3V;
C、VGSQ=1V,IDQ=0.1mA,VDSQ=3V;
D、VGSQ=2V,IDQ=1mA,VDSQ=3V;
10、In the circuit in Figure，the MOSFET worked in which Region? ( )
A、cutoff
B、saturation
C、nonsauration
D、Indeterminate
11、In the circuit in Figure，the MOSFET worked in which Region? ( )
A、cutoff
B、saturation
C、nonsauration
D、Indeterminate
12、In the circuit in Figure， VGSQ=（ ）V，ID=（ ）mA，VDS=( )V;
A、VGSQ=4V,IDQ=4mA,VDSQ=-2V;
B、VGSQ=4V,IDQ=1mA,VDSQ=7V;
C、VGSQ=3V,IDQ=1mA,VDSQ=6V;
D、VGSQ=4V,IDQ=1mA,VDSQ=3V;
13、In the circuit in Figure， VGSQ=（ ）V，ID=（ ）mA，VDS=( )V;
A、VGSQ=4V,IDQ=4mA,VDSQ=-2V;
B、VGSQ=4V,IDQ=1mA,VDSQ=7V;
C、VGSQ=3V,IDQ=1mA,VDSQ=6V;
D、VGSQ=3V,IDQ=1mA,VDSQ=2.5V;
14、In the circuit in Figure，the MOSFET worked in which Region? ( )
A、cutoff
B、saturation
C、nonsauration
D、Indeterminate
15、In the circuit in Figure，the MOSFET worked in which Region? ( )
A、cutoff
B、saturation
C、nonsauration
D、Indeterminate
16、In the circuit in Figure， VGSQ=（ ）V，ID=（ ）mA，VDS=( )V;
A、VGSQ=2V,IDQ=2mA,VDSQ=2.8V;
B、VGSQ=2.2V,IDQ=1mA,VDSQ=7.2V;
C、VGSQ=2V,IDQ=2mA,VDSQ=6V;
D、VGSQ=2.2V,IDQ=1mA,VDSQ=2.2V;
17、Which MOSFETs can work as amplifiers in the following circuits.
A、A
B、B
C、C
D、D
E、E
18、The gate source voltage and the drain source voltage are as follows, and VTN, VTP or VPN, VPP values are also known.which MOSFETs work in cutoff region （ ）
A、VDS＝3V， VGS＝2V， VTN＝1V
B、VDS＝3V， VGS＝1V， VTN＝1.5V
C、VDS＝3V， VGS＝－1V， VPN＝－2V
D、VDS＝－3V， VGS＝－2V， VTP＝－1V
E、VDS＝3V， VGS＝－2V， VTP＝－1V
F、VDS＝－3V， VGS＝－1V， VTP＝－1.5V
19、The gate source voltage and the drain source voltage are as follows, and VTN, VTP or VPN, VPP values are also known.which MOSFETs work in saturation region （ ）
A、VDS＝3V， VGS＝2V， VTN＝1V
B、VDS＝3V， VGS＝1V， VTN＝1.5V
C、VDS＝3V， VGS＝－1V， VPN＝－2V
D、VDS＝－3V， VGS＝－2V， VTP＝－1V
E、VDS＝3V， VGS＝－2V， VTP＝－1V
F、VDS＝－3V， VGS＝－1V， VTP＝－1.5V
20、For n-channel and p-channel MOSFETs, the drain source voltage VDS can be positive or negative value.
21、For n-channel depletion-mose MOSFETs, the gate source voltage VGS must be positive in order to get the MOSFETs work in the saturation region.
22、The threshold voltage of p-channel and n-channel enhancement-mode MOSFETs must be positive.
Lecture 4 Basic FET Amplifiers
Test questions for Basic FET Amplifiers
1、Assuming that the capacitors in the circuit are very large and can be regarded as short circuit to AC signal, the small signal equivalent circuit is （ ）?
A、
B、
C、
D、
2、Assuming that the DC operating points of all the following amplifier circuits are normal, all of the capacitors to AC signal can be regarded as a short circuit, and the circuit with the largest input resistance is （ ）.
A、
B、
C、
D、
E、
3、Assuming that the DC operating points of all the following amplifier circuits are normal, all of the capacitors to AC signal can be regarded as a short circuit, and which circuit has the lowest input resistance （ ）
A、
B、
C、
D、
E、
4、Assuming that the DC operating points of all the following amplifier circuits are normal, all of the capacitors to AC signal can be regarded as a short circuit, and which circuit has the lowest output resistance （ ）
A、
B、
C、
D、
5、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. The gm of T1 is gm=1mS.Determine the voltage gain of the circuit Av=vo/vi=（ ）
A、3.3
B、-3.3
C、-10
D、-0.77
6、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. Determine the voltage gain of the circuit Av=vo/vi=（ ）
A、3
B、-3
C、6
D、-6
7、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. Determine the voltage gain of the circuit Av=vo/vi=（ ）
A、3
B、-3
C、1
D、-1
8、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. Determine the voltage gain of the circuit Av=vo/vi=（ ）
A、3
B、-3
C、6
D、-6
9、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. Determine the voltage gain of the circuit Av=vo/vi=（ ）.
A、6
B、-6
C、2
D、-2
10、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. Determine the voltage gain of the circuit Av=vo/vi=（ ）
A、3
B、-3
C、6
D、-6
11、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. Determine the voltage gain of the circuit Av=vo/vi=（）.
A、-0.89
B、0.89
C、10
D、-10
12、Assuming that the DC operating points of all the following amplifier circuits are normal, all of the capacitors to AC signal can be regarded as a short circuit, and which circuits have output and input signals in phase（ ）
A、
B、
C、
D、
E、
13、Assuming that the DC operating points of all the following amplifier circuits are normal, all of the capacitors to AC signal can be regarded as a short circuit, and which circuits have output and input signals opposite phase（ ）
A、
B、
C、
D、
E、
14、In the multistage amplifier circuit, the input resistance is the input resistance of the first stage, and the output resistance of the amplifier circuit is equal to the output resistance of the last stage (output stage).
15、Because the voltage gain of common drain amplifier circuit is less than 1, it cannot be used in the amplifier circuit
16、Because the structures of n-channel enhancement MOSFET and p-channel enhancement MOSFET are different, the DC bias of amplifier circuit is different, and the small model used in AC analysis is also different.
17、The field effect transistor (FET) works in the saturation region and can be used as an amplifier. The AC amplification performance is independent of the DC operating point.
18、The threshold voltage and transconductance of enhancement MOSFET are constant.
19、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. The gm of T1 is gm=1mS.Determine the input resistance is（ ）kohm.
20、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit.Determine the output resistance is ( ) ohm.
21、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit.Determine the input resistance is ( )ohm.
22、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit.Determine the source voltage gain of the circuit Av=vo/vs=( ).
23、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit.Determine the output resistance is ( )k ohm.
Lecture 5 The Bipolar Junction Transistor
Test questions for The Bipolar Junction Transistor
1、When a BJT transistor is used as an amplifying device, the base-emitter junction is ( ) biased, and the base-collector junction is ( ) biased.
A、Forward，forward
B、Reverse, reverse
C、Forward, reverse
D、Reverse, forward
2、For the impurity doping concentrations in the three regions of the BJT, which region is the highest ( )
A、base
B、emitter
C、collect
D、unidentified
3、When a BJT transistor worked in saturation region, the base-emitter junction is ( ) biased, and the base-collector junction is ( ) biased.
A、Forward，forward
B、Reverse, reverse
C、Forward, reverse
D、Reverse, forward
4、A transistor is biased in the forward-active mode, the current of the three terminals are I1= –1.2mA, I2= –0.03mA, I3= 1.23mA，which of these is the emitter terminal ( )，and which of these is the base terminal ( )
A、1，2
B、2，3
C、3,2
D、3,1
5、In a BJT circuit, the transistor are made of silicon, and the voltage values for three terminals are given, which BJT operates in forward-active mode ( )
A、VC=6V ,VB=0.7V, VE=0V
B、VC=6V , VB=6V , VE=5.4V
C、VC=6V ,VB=4V ,VE=3.6V
D、VC=3.6V ,VB=4V ,VE=3.4V
6、In a BJT circuit, the transistor are made of silicon, and the voltage values for three terminals are given, which BJT operates in cutoff region ( )（For silicon transistor，we think VBE（th）=0.5V）
A、VC=6V ,VB=0.7V, VE=0V
B、VC=6V , VB=6V , VE=5.4V
C、VC=6V ,VB=4V ,VE=3.6V
D、VC=3.6V ,VB=4V ,VE=3.4V
7、In the amplification circuit, the BJT is worked in forward-active region, and the voltage of each terminals is V1=2V, V2=6V and V3=2.7V, for the three terminals, which is the emitter ( ), the type of this transistor is ( ).
A、3, NPN
B、2, PNP
C、1,NPN
D、1, PNP
8、For the circuit shown in Figure, which region does the transistor work in ( )
A、Forward-active region
B、Saturation region
C、Cutoff region
D、unidentified
9、For the circuit shown in Figure, which region does the transistor work in ( )
A、Forward-active region
B、Saturation region
C、Cutoff region
D、unidentified
10、For the circuit shown in Figure, which region does the transistor work in ( )
A、Forward-active region
B、Saturation region
C、Cutoff region
D、unidentified
11、For the circuit shown in Figure, if the input signal is a good sinusoidal signal, but the output waveform is in the Figure 16, so this is which distortion ( )
A、no distortion
B、Saturation region
C、Cutoff region
D、unidentified
12、A transistor is biased in the forward-active mode, the current of the three terminals are I1= –1.2mA, I2= –0.03mA, I3= 1.23mA，the current gain β is ( )
A、30
B、40
C、50
D、60
13、In a BJT circuit, the transistor are made of silicon, and the voltage values for three terminals are given, which BJT operates in saturation region ( )
A、VC=6V ,VB=0.7V, VE=0V
B、VC=6V , VB=6V , VE=5.4V
C、VC=6V ,VB=4V ,VE=3.6V
D、VC=3.6V ,VB=4V ,VE=3.4V
14、For the circuit shown in Figure, if the input signal is a good sinusoidal signal, but the output waveform is in the Figure, so what measures can be taken to eliminate such distortion ( )
A、increase VCC amplitude
B、reduce the amplitude of signal source
C、reduce the value of load resistance RL
D、open the load
15、If the emitter and collector of BJT transistor are exchanged, the amplifier can still be constructed.
16、When NPN transistor works in the forward active region, generally we added positive power supply, but for PNP transistor, we must add negative power supply.
17、For the circuit shown in Figure, the operational amplifier is assumed to be ideal, for the transistor VBE=VB-VE=0.7V, if the reading of the voltmeter is 200mV,then the current gain β of the transistor is ( )
Lecture 6 Basic BJT Amplifiers
Test questions for Basic BJT Amplifiers
1、For the circuit shown in Figure, determine the small signal hybrid-π resistance rπ is ( )and the voltage gain is （ ）
A、2.6k ohm,200
B、2.6k ohm, -200
C、2.6 ohm, 200000
D、2.6 ohm, -200000
2、For all of the circuits shown in Figure, which circuit can amplify AC small signal ( )
A、(a)
B、(b)
C、(c)
D、(d)
3、For the circuit shown in Figure, which position is the switch in A, B, C? the transistor can work in the forward active region ( )
A、A
B、B
C、C
D、Unable to determine
4、For the circuit shown in Figure, if the transistor works in the forward active region, which output waveform is correct ( )
A、
B、
C、
D、
5、For the circuit shown in Figure, if the transistor works in the forward active region, which output waveform is correct ( )
A、
B、
C、
D、
6、If the source resistance of the signal source is 1kohm，and when the amplifying circuit is not connected,the voltage amplitude of the signal source is 10mV， but when the amplifying circuit is connected,the voltage of the input port of the amplifying circuit is 8mV， then the input resistance of the amplifying circuit is ( )k ohm.
A、5
B、4
C、2
D、1
E、0.5
7、For the amplifier, when the load is open,the output voltage is 4V, and when the 3k ohm load resistor is connected, the output voltage is 3V, then the output resistance of the amplification circuit is ( )k ohm.
A、5
B、4
C、2
D、1
8、For the amplifier, when the input signal is 10pA current and the output is 500mV voltage, the input resistance of this amplifier is better if it is larger or smaller, and the the output resistance of this amplifier is better if it is larger or smaller( )
A、smaller,larger
B、smaller, smaller
C、larger, larger
D、larger, smaller
9、For the circuit shown in Figure，the voltage gain is （ ）,and the input resistance is ( )k ohm, output resisdtance is ( ) k ohm.
A、145,300,1
B、-145, 0.69,2
C、290,0.69,2
D、-145,0.69,1
10、For the circuit shown in Figure，the voltage gain is （ ）,and the input resistance is ( )k ohm, output resisdtance is ( ) k ohm.
A、87,1.55,3
B、-87, 1.55,3
C、174,1.55,1.5
D、-174,1.55,1.5
11、For the circuit shown in Figure，when the 50uF capacitor is open, the the voltage gain is will ( ) and the input resistance will ( ), output resisdtance will ( ).
A、increase, decrease, unchanged
B、decrease, increase, unchanged
C、decrease,decrease,decrease
D、increase,increase,increase
12、For the circuit shown in Figure ，the voltage gain is （ ）,and the input resistance is ( )k ohm, output resisdtance is ( ) ohm.
A、0.99,87.2,5.1k
B、0.99, 87.2, 33
C、0.99,260,2.55k
D、99,87.2,2.55k
13、For the circuit shown in Figure，when the ouput voltage is Vo1, the source voltage gain Vo1/vs is （ ）,and the input resistance is ( )k ohm, output resisdtance is ( ) ohm.
A、0.79,82,2k
B、-0.79, 8.2, 2k
C、0.8,82,31
D、-0.8,8.2,1k
14、For the circuit shown in Figure ，when the ouput voltage is Vo2, the source voltage gain is （ ）,and the input resistance is ( )k ohm, output resisdtance is ( ) ohm.
A、0.79,82,2k
B、-0.79, 8.2, 2k
C、0.8,8.2,31
D、-0.8,8.2,1k
15、For the circuit shown in Figure，the voltage gain is （ ）,and the input resistance is ( )k ohm, output resisdtance is ( ) ohm.
A、-291,2.574,7.5k
B、291, 0.025, 7.5k
C、-291,25,7.5k
D、291,25,7.5k
16、In the following circuits,which circuit has the least input resistance ( )
A、
B、
C、
D、
17、In the following circuits,which circuit has the least output resistance.( )
A、
B、
C、
D、
18、In the following circuits,which circuit has the largest absolute gain. ( )
A、
B、
C、
D、
19、For the circuit shown in Figure, if the DC voltage VCE≈VCC, what may be wrong with the circuit?
A、The capacitor Cb1 is short
B、The resistor Rb is open
C、The resistor RC is short
D、The resistor Rb is short
E、The resistor RC is open
20、For the circuit shown in Figure, if the transistor works in the forward active region, which small signal equivalent circuit is correct ( )
A、
B、
C、
D、
E、
F、
21、Which of the following amplifying circuits may amplify the signal AC voltage ( )
A、CE
B、CC
C、CB
D、CS
E、CD
F、CG
22、Which of the following amplifying circuits may amplify the signal AC current ( )
A、CE
B、CC
C、CB
D、CG
E、CD
F、CS
23、In the following circuits,which circuits have output voltage and input voltage in phase.( )
A、
B、
C、
D、
24、In the following circuits,which circuits have inverse output and input voltages.( )
A、
B、
C、
D、
E、
25、When a BJT transistor is biased in the forward-active mode, then iC=β* iB, so we can think of transistors as always linear devices.
26、Use the BJT, we can magnify an input small signal to a large output signal, we don't need DC power supply.
27、As long as the transistor works in the forward active region, no matter how large the input signal is, linear amplification can be realized.
28、Because of the different structure of NPN and PNP, the DC biasing is different when they work in forward active region, so the small signal model is different
29、The capacitor can be open for dc, and can be short for any signal frequency.
30、The independent source can always become a short circuit for ac analysis.
31、For the BJT, when the Early voltage VA is not infinite， we’re dealing with small-signal amplifiers, we also say that the collector current of a BJT in active mode is equal to the base current multiplied by β.
32、For the circuit with emitter bypass capacitor, this bypass capacitor not only changes the Q-point, but also affects the small signal voltage gain.
33、Because the small signal voltage gain of the common collector circuit is less than 1, it has no contribution to signal amplification.
34、The common collector circuit can neither amplify voltage nor current.
35、For the circuit shown in Figure ，whether the output voltage waveform is correct（ ）
Lecture 7 Frequency Response
Test questions for Frequency Response
1、In a single stage common-emitter circuit, at the corner frequency of fH, the phase of voltage gain φ(f) is ( ) degree.
A、-45
B、-135
C、-180
D、-225
2、If the frequency f is nearly zero , the voltage gain of the circuit is equal the pass-band voltage gain, then the circuit may be ( )
A、low-pass filter
B、high-pass filter
C、bandpass filter
D、band-reject filter
3、Consider the circuit in the figure, what is the time constant τ associated with this circuit? and this circuit is high-pass circuit or low-pass circuit?
A、0.05s, high-pass
B、0.05s, low-pass
C、0.2s, high-pass
D、0.2s, low-pass
4、Consider the circuit in the figure, what is the time constant τ associated with this circuit? and this circuit is high-pass circuit or low-pass circuit?
A、0.05s, high-pass
B、0.05s, low-pass
C、0.2s, high-pass
D、0.2s, low-pass
5、The magnitude frequency response of an amplifier circuit is shown in the figure, so the upper corner frequency is （ ）, the lower corner frequency is （ ）, and the passband gain is （ ）.
A、100Hz，50000Hz，5dB
B、100Hz，50000Hz，5
C、100rad/s，50000rad/s，5
D、100rad/s，50000rad/s，5dB
6、The transfer function corresponding to the Bode plot of the magnitude shown in figure,what is the actual gain at 100Hz.
A、60dB
B、57dB
C、40dB
D、63dB
7、In high frequency range, drop in gain is caused by ( )
A、bypass capacitors
B、coupling capacitors
C、transistor's parasitic capacitors
D、bias resistors
8、When the signal frequency f is equal to the corner frequency fL or fH, the gain is ( ) times as big as the maximum midband gain.
A、0.5
B、0.707
C、0.9
D、1.414
9、In a two-stage amplifier circuit, if 20log|AVM1|=40dB, and fL1=4Hz,fH1=20kHz, 20log|AVM2|=30dB,fL2=400Hz，fH2=150kHz， the for the two-stage amplifier， the total voltage gain is （ ），and the lower corner frequency is （ ）， the upper corner frequency is （ ）
A、70， 4Hz，20kHz
B、70dB， 400Hz， 20kHz
C、70，400Hz， 20kHz
D、70dB， 4Hz， 150kHz
10、Consider the circuit in the figure, what is the time constant τ associated with Cb1?
A、11ms
B、21ms
C、1ms
D、10ms
11、Consider the circuit in the figure, what is the time constant τ associated with Cc?
A、8ms
B、4ms
C、2ms
D、10ms
12、A zero of the transfer function T(s)=10*(s+1)/[(s+2)*(s+3)] is at （ ）
A、10
B、-1
C、-2
D、-3
13、On the Bode magnitude plot, the slope of 1/[(5+jw)(5+jw)] for large values of w is ( )
A、20dB/decade
B、40dB/decade
C、-20dB/decade
D、-40dB/decade
14、The difference between the half-power frequencies is called the ( )
A、quality factor
B、resonant frequency
C、bandwidth
D、cutoff frequency
15、In low frequency range, drop in gain is caused by ( )
A、bypass capacitors
B、coupling capacitors
C、transistor's parasitic capacitors
D、bias resistors
16、To find the maximum gain magnitude of the amplifier ( )
A、Coupling and bypass capacitors act as shorts
B、transistors' junction capacitances act as opens
C、Coupling and bypass capacitors act as opens
D、transistors' junction capacitances act as shorts
17、In order to reduce the lower corner frequency of the circuit shown in the figure, and without changing the passband gain, the following measures can be taken ( )
A、increase Cb1,Cb2
B、increase Ce
C、decrease Cb1,Cb2
D、decrease Ce
E、increase Rc
18、The poles of the transfer function T(s)=10*(s+1)/[(s+2)*(s+3)] is at （ ）
A、10
B、-1
C、-2
D、-3
19、The difference between direct coupled amplifier and RC coupled amplifier is that its gain in low frequency region will not be attenuated.
20、The lower corner frequency of the amplifier circuit can be reduced by selecting the transistor with small junction capacitance.
21、Bandwidth can be increased by reducing the gain of the amplifier circuit.
22、Consider the circuit in the figure, if the 50uF bypass capacitor is connected to the circuit, then the bandwidth of this amplifier can be increased.
23、Generally, the bandwidth of common gate and common base amplifier is wider than that of common source and common emitter amplifier.
Lecture 8 Output Stages and Power Amplifiers
Test questions for Output Stages and Power Amplifiers
1、The reason for the low efficiency of class a amplifier is （ ）
A、The ICQ quiescent current is too large
B、The ICQ quiescent current is too small
C、The VCEQ quiescent voltage is too large
D、The VCEQ quiescent voltage is too small
2、In a multistage amplifier, the power amplifier usually used in the （ ）stage.
A、input stage
B、output stage
C、intermediate stage
D、any stage
3、Among the following amplifiers, the most high efficiency is which circuit （ ）
A、class A amplifiers
B、class AB amplifiers
C、class B amplifiers
D、CE amplifiers
4、If the maximum output power of a class B power amplifier is 20W, the maximum power of each power transistor shall be at least ( ).
A、20W
B、10W
C、4W
D、2W
5、Assume the transistor has limiting factors of: IC(max)=5A,VCE(max)=30V, and PT(max)=25W,and consider the common-emitter circuit shown in Figure, if VCC=24V, then the maximun collect current ICM=( ).
A、6A
B、1A
C、5A
D、10A
6、For the circuit shown in figure, the BJT transistor parameters are VBE(on)=0.7V,VCE(sat)=1V, VA=∞,so the maximum collector-emitter voltage is( )
A、24V
B、23V
C、11.7V
D、12V
7、For the circuit shown in figure,when the input voltage is negative half cycle, then ( )
A、T1 on，T2 off
B、T1 on，T2 on
C、T1 off，T2 on
D、T1 off，T2 off
8、Consider the circuit in Figure, for the transistor, the saturation voltage VCES=1V, and the DC supply voltage is VCC=15V, and the load resistance RL= 8ohm, the the maximum power of the load maybe ( )
A、14W
B、28W
C、12.25W
D、24.5W
9、For the circuit shown in figure ,the function of the two diodes in the circuit is ( )
A、convert AC to DC
B、convert DC to AC
C、filtering out unnecessary signals
D、get a constant DC bias voltage
10、For the circuit shown in Figure, ignored the saturation of the transistor ,then the maximum power of the load maybe ( ).
A、9W
B、4.5W
C、14W
D、28W
11、For the circuit shown in Figure, ignored the saturation of the transistor ,then the maximum power of each transistor maybe ( )
A、9W
B、4.5W
C、0.9W
D、1.8W
12、For the circuit shown in Figure, ignored the saturation of the transistor ,then the maximum collector-emitter voltage of the transistor maybe ( )
A、12V
B、24V
C、6V
D、18V
13、Which of the following classes is generally used for low-frequency power amplifier ( )
A、A
B、B
C、C
D、D
14、In a FM stereo receiver, the audio amplifier may be ( ).
A、class-A amplifier
B、class-B amplifier
C、class-AB amplifier
D、class-C amplifier
15、The maximum possible efficiency of the class-B amplifiers is ( ).
A、25%
B、50%
C、78.5%
D、100%
16、Which of the following amplifiers can be used as power output stages （ ）.
A、CE
B、CB
C、CC
D、CD
E、CG
F、CS
17、For the Class-B push-pull complementary output stages, when the load get the maximum output power, the transistor also reach to the maximum value.
18、Among the three class of amplifiers, class A, class B and class AB, class B amplifier has the highest efficiency, so the actual power amplifier is generally realized by class B amplifier.
19、Because the power amplifier must be requred a large amount of output power, it is usually realized by common emitter circuit.
20、Because the input and output of the power amplifiers are sinusoidal signals of the same frequency, so we usually use the small signal model to analysis.
21、The output waveform of class A amplifier is not distorted, but the efficiency is too low, and it is not used as the output stage.
Lecture 9 Integrated Circuit Biasing and Active Loads
Test questions for Integrated Circuit Biasing and Active Loads
1、For the circuit in Figure, VBE3=VBE4=0.6V, the current IC4 is （ ）
A、0.5mA
B、1mA
C、2mA
D、3mA
2、For the circuit in Figure, the current IREF is( )mA, the current IO is( )mA.
A、2.25，0.9
B、22.5，0.9
C、1，0.1
D、5，0.2
3、For the circuit in Figure, VBE3=VBE4=0.7V, the current Io is ( )
A、0.5 mA
B、1mA
C、0.86mA
D、2mA
4、The circuit is shown as Figure, assume β>>1, T1 and T2 are same transistor, VCC=VEE=5V,VBE=0.6V,then IO=( )mA.
A、9.4
B、0.94
C、1.94
D、0.094
5、The circuit is shown as Figure,for all of the transistors，assume β>>1，VBE=0.7V,then the DC current IE2=( )mA.
A、1
B、1.1
C、1.2
D、1.3
6、The circuit is shown as Figure ,for all of the transistors，assume β>>1，and then neglect the base currents,for NPN VBE=0.6V,and for PNP, VEB=0.6V,then the reference current IREF=( )mA.
A、1
B、0.1
C、0.2
D、0.5
7、The circuit is shown as Figure,for all of the transistors，assume beta>>1，and then neglect the base currents,for NPN VBE=0.6V,and for PNP, VEB=0.6V,then the current IO2=( )mA.
A、1
B、0.1
C、0.2
D、0.5
8、The circuit is shown as Figure,for all of the transistors，assume beta>>1，andthen neglect the base currents,for NPN VBE=0.6V,and for PNP, VEB=0.6V,then the current IO4=( )mA.
A、1
B、0.1
C、0.2
D、0.3
9、The circuit is shown as Figure,how many current sources are there in the figure( )
A、2
B、3
C、4
D、5
10、Consider the circuit in Figure, the current IREF= ( )mA
A、1
B、2
C、3
D、4
11、Consider the circuit in Figure , the current IO1= ( )mA.
A、1
B、2
C、3
D、4
12、Consider the circuit in Figure, the current IO2= ( )mA.
A、1
B、2
C、3
D、4
13、Consider the circuit in Figure, the current IO3= ( )mA.
A、1
B、2
C、3
D、4
14、Consider the circuit in Figure, the reisitor RE1= ( )k ohm.
A、0.5
B、0.75
C、1.5
D、3
15、Consider the circuit in Figure, the reisitor RE2= ( )k ohm
A、0.5
B、0.75
C、1.5
D、3
16、Consider the circuit shown in Figure, the transistor parameters and the W/L ratios are given in the figure, then IREF= ( )mA.
A、0.4248
B、0.1805
C、0.0361
D、0.2256
17、Consider the circuit shown in Figure, the transistor parameters and the W/L ratios are given in the figure, then I1= ( )mA.
A、0.4248
B、0.1805
C、0.0361
D、0.2256
18、Consider the circuit shown in Figure, the transistor parameters and the W/L ratios are given in the figure, then I2= ( )mA.
A、0.4248
B、0.1805
C、0.0361
D、0.2256
19、The output current of the current source is constant, and its AC equivalent resistance is （ ）
A、zero
B、less than DC equivalent resistance
C、same to DC equivalent resistance
D、more and more greater than DC equivalent resistance
E、maybe infinite
20、Which of the following are the basic characteristics of the current source( )
A、Output current is constant
B、The DC equivalent resistance is very large
C、The AC equivalent resistance is very large
D、The DC equivalent resistance is nearly zero
E、The AC equivalent resistance is nearly zero
21、Using current source as active loads instead of resistance can increase voltage gain of the amplifier.
22、The output current of current source is constant, so it has no effect on AC amplification.
23、The current source can also input AC signal for amplification.
Lecture 10 Differential and Multistage Amplifiers
Test questions for Differential and Multistage Amplifiers
1、For the circuit in Figure, the DC voltage VCE4 is（ ）V
A、1.7
B、2.7
C、3.7
D、4.7
2、The goal of the design of the differential amplifiers is to ( ).
A、improve the voltage gain
B、minimize the effect of the common-mode input signal
C、increase the input resistance
D、decrease the output resistance
3、Consider the circuit shown in Figure. The bipolar transistor parameters are β=100, VBE(on)=0.7V ,VA=∞ for T1 and T2, the T3 and T4 are identical.When RL=∞, determine the differential-mode voltage gain Avd2=vo2/vi=( ).
A、49.7
B、-49.7
C、24.85
D、-24.85
4、Consider the circuit shown in Figure. The bipolar transistor parameters are β=100,VBE(on)=0.7V ,VA=∞ for T1 and T2, the T3 and T4 are identical.Determine the differential-mode input resistance Rid=( )k ohm.
A、16.3
B、32.6
C、10.4
D、12.4
5、Consider the circuit shown in Figure. The bipolar transistor parameters are β=100,VBE(on)=0.7V ,VA=∞ for T1 and T2, the T3 and T4 are identical.When RL=∞, determine the differential-mode voltage gain Avd2=vo2/vi=( ).
A、130.6
B、-130.6
C、65.3
D、-65.3
6、Consider the circuit shown in Figure. The bipolar transistor parameters are β=100,VBE(on)=0.7V ,VA=∞ for T1 and T2, the T3 and T4 are identical.Determine the differential-mode input resistance Rid=( )k ohm
A、16.3
B、32.6
C、10.4
D、12.4
7、Consider the circuit shown in Figure. The bipolar transistor parameters are β=100,VBE(on)=0.7V ,VA=∞ for T1 and T2, the T3 and T4 are identical.When RL=∞, determine the differential-mode voltage gain Avd2=vo2/vi=( )
A、155.77
B、-155.77
C、77.88
D、-77.88
8、Consider the circuit shown in Figure. The bipolar transistor parameters are β=100,VBE(on)=0.7V ,VA=∞ for T1 and T2, the T3 and T4 are identical.Determine the differential-mode input resistance Rid=( )k ohm.
A、16.3
B、32.6
C、10.4
D、12.4
9、Consider the circuit shown in Figure, when two-sided output, the differential-mode voltage gain is vo/vi=-10, and the common-mode voltage gain is very very small, we can not consider this, which output waveform is right ( ).
A、A
B、B
C、C
D、D
10、The common mode rejection ratio of differential amplifier means( )
A、Ability to suppress zero drift
B、Driving load capacity
C、The value of differential mode gain
D、The value of common mode gain
11、Consider the differential amplifier shown in figure, The phases of vG1 and vo1 are ( ),and the phases of vG1 and vo2 are( ).
A、in phase, in phase
B、opposite phase,in phase
C、in phase, opposite phase
D、opposite phase, opposite phase
12、Consider the differential amplifier shown in figure,in the AC equivalent circuit with common mode input signal, the effect of Rs on half circuit is equivalent to( )
A、short
B、open
C、2Rs
D、Rs
13、Consider the differential amplifier shown in figure ,in the AC equivalent circuit with differential mode input signal, the effect of Rs on half circuit is equivalent to( )
A、short
B、open
C、2Rs
D、Rs
14、Consider the differential amplifier shown in figure ,when two-sided output, and vo=vo1-vo2,the expression of differential mode voltage gain is （ ）
A、-β*Rc/rπ
B、β*Rc/rπ
C、-β*Rc/(rπ+Rb)
D、β*Rc/(rπ+Rb)
15、For a differential amplifier,the two inputs vi1=30mV, and vi2=10mV,when one-sided output, the output voltage is vo2=1V, and the CMRR= ∞, so the value of differential mode voltage gain is ( )
A、30
B、40
C、50
D、60
16、The circuit is shown in the figure，then the differential mode voltage gain Avd2=vo2/vid=( ), the CMRR is ( )
A、3.85, 77
B、3.85, 110
C、-3.85, 77
D、-3.85, 110
17、The circuit is shown in the figure，when the circuit is two-sided output,then the differential mode voltage gain Avd=(vo1-vo2)/vid=( ), the CMRR is ( )
A、7, ∞
B、-7, ∞
C、-7.7, ∞
D、7.7, ∞
18、which of the following are the characteristics of differential amplifier circuit （ ）
A、Both the difference mode voltage gain and common mode voltage gain of the circuit are very large;
B、Usually the difference mode voltage gain maybe not very large,but the common mode voltage gain is very very small;
C、The circuit is well matched;
D、The circuit has a strong ability to reject noise;
E、Both the difference mode voltage gain and common mode voltage gain of the circuit are very small;
19、Consider the differential amplifier shown in figure,the main function of RE in the circuit is( )
A、Improve the input resistance of differential mode；
B、Increase common mode input resistance；
C、Increase differential mode voltage gain；
D、Increase common mode voltage gain；
E、Improve common mode rejection ratio CMRR；
20、The circuit is shown in the figure. If the| vo/v1|=10, the common mode gain is very small and can be think its zero，What is the correct output voltage waveform in the figure.
A、A
B、B
C、C
D、D
E、E
F、F
21、Mismatching of differential amplifier will reduce the common mode rejection ratio.
22、For differential-mode voltage gain analysis, the one-sided input of differential amplifier is equivalent to the two-sided input.
23、The one-sided output of differential amplifier is equivalent to the two-sided output.
24、The CMRR is a parameter to express the voltage amplification ability of amplifier circuit.
25、Consider the differential amplifier shown in figure, if CMRR=100, and Avd2=vo2/v1=100, v1=20mV, then the ac output vo2=( )mV;
Lecture 11 Feedback and Stability
Test questions for Feedback and Stability
1、For amplification circuits, open loop means ( )
A、No DC power supply
B、No signal source
C、No feedback path
D、No load
2、For amplification circuits, closed loop means ( )
A、With signal source
B、With feedback path
C、With DC power supply
D、With load
3、Find out the feedback path in the circuit shown in the figure and which is positive feedback.
A、A
B、B
C、C
D、D
4、Find out the feedback path in the circuit shown in the figure and which is only ac feedback.
A、A
B、B
C、C
D、D
5、Find out the feedback path in the circuit shown in the figure and determine this feedback configuration is ( )
A、negative series-shunt feedback
B、negative shunt-shunt feedback
C、positive series-shunt feedback
D、negative shunt-series feedback
6、For the circuit shown in Figure, the feedback path Rf2-Rf1 is ( )
A、ac negative feedback
B、DC negative feedback
C、ac positive feedback
D、DC positive feedback
7、For the circuit shown in Figure, the feedback path T3-Re1 is ( )
A、ac positive feedback
B、DC positive feedback
C、ac and DC positive feedback
D、ac and DC negative feedback
8、For the circuit shown in Figure, the ac feedback between two stages is ( )
A、Shunt-shunt
B、Shunt-series
C、Series-shunt
D、Series-series
9、For the circuit shown in Figure, the feedback path T3-Rf2-T1 is ( )
A、ac positive feedback
B、DC positive feedback
C、ac and DC positive feedback
D、ac and DC negative feedback
10、For the circuit shown in Figure, the feedback path T2-Rf1-T1 is ( )
A、DC positive feedback
B、ac positive feedback
C、ac negative feedback
D、DC negative feedback
11、If the output current of the feedback circuit tends to be stabilized, and the input resistance tends to be increased, which negative feedback should be used ( ).
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
12、Consider the feedback circuit in Figure , determine the feedback (T3-T1) configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
13、Consider the feedback circuit in Figure, determine the feedback between two stages configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
14、Consider the feedback circuit in Figure, determine the feedback between two stages configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
15、Consider the feedback circuit in Figure , determine the feedback between two stages configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
16、Consider the feedback circuit in Figure, determine the feedback configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
17、Consider the feedback circuit in Figure, compared with the open loop Ri and Ro, determine the closed-loop Rof and Rif will( )
A、increase, decrease
B、decrease,increase
C、increase, increase
D、decrease, decrease
18、Consider the feedback circuit in Figure, determine the feedback between two stages configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
19、Consider the feedback circuit in Figure, if |1+Aβ|>>1,determine the closed-loop gain io/is is ( )
A、-8.8
B、8.8
C、-5
D、-6
20、Consider the feedback circuit in Figure, determine the feedback between two stages configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
21、Consider the feedback circuit in Figure, if |1+Aβ|>>1,determine the closed-loop gain io/vs is ( )
A、98ms
B、100ms
C、-100ms
D、-98ms
22、Consider the feedback circuit in Figure, determine the feedback between two stages configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
23、Consider the feedback circuit in Figure , if |1+Aβ|>>1,determine the closed-loop gain vo/is is ( )
A、25k ohm
B、-25k ohm
C、5k ohm
D、-5k ohm
24、Consider the feedback circuit in Figure, determine the feedback between two stages configuration is ( )
A、Shunt-Shunt
B、Shunt-Series
C、Series-Shunt
D、Series-Series
25、In the case of constant input, if feedback is introduced, which means that negative feedback is introduced.
A、output increase
B、input resistance increase
C、net input increase
D、net input decrease
E、output decrease
26、Which of the following are the advantages of negative feedback?( )
A、the closed-loop gain decreases
B、the circuit may oscillate
C、Gain sensitivity is improved
D、Can extand bandwidth
E、Can reduce nonlinear distortion
27、Which of the following are the disadvantages of negative feedback?( )
A、the closed-loop gain decreases
B、the circuit may oscillate
C、Gain sensitivity is improved
D、Can extand bandwidth
E、Can reduce nonlinear distortion
28、Find out the feedback path in the circuit shown in the figure and which is negative feedback.
A、A
B、B
C、C
D、D
29、When negative feedback is introduced into the amplifying circuit, the gain will decrease, so the introduction of negative feedback is not good for the amplifying circuit.
30、The loop gain is just the closed-loop gain.
31、In the following circuits, there is only one feedback path between two stages.
32、In the following circuits, the feedback is only ac feedback.
33、For the negative and series output feedback, it can reduce the output resistance.
34、For the series input and negative feedback, the smaller the resistance of the signal source, the better the feedback effect.
35、The input voltage of an amplifier is 1mV and the output voltage is 1V. After adding negative feedback, when the output signal remains unchanged, the input signal to be added is 10mV. What is the feedback coefficient of the circuit( )
36、If the open-loop gain of an amplifier is 10000 and the closed-loop gain is 20, then the feedback coefficient is （ ）
37、Consider the feedback circuit in Figure, if |1+Aβ|>>1,determine the closed-loop voltage gain is ( )
38、Consider the feedback circuit in Figure , if |1+Aβ|>>1,determine the closed-loop voltage gain is ( )
39、Consider the feedback circuit in Figure, if |1+Aβ|>>1,determine the closed-loop voltage gain is ( )
40、Consider the ideal series-shunt circuit shown in figure， Let Av=5000V/V,β=0.008V/V, Ri=10k ohm, Ro=1k ohm, then Rif=( )k ohm.
41、Consider the feedback circuit in Figure, if |1+Aβ|>>1,determine the closed-loop voltage gain vo/vs is ( )
Lecture 12 Applications and Design of Integrated Circuits
Test questions for Applications and Design of Integrated Circuits
1、If the signal frequency is lower than 20Hz, what filter should be selected？
A、Low-pass filter
B、High-pass filter
C、Band pass filter
D、Band-reject filter
2、What kind of filter should be selected to reject the interference of 50 Hz AC power supply?
A、Low-pass filter
B、High-pass filter
C、Band-pass filter
D、Band-reject filter
3、When the signal frequency from 500Hz to 50kHz, what kind of filter should be selected?
A、Low-pass filter
B、High-pass filter
C、Band-pass filter
D、Band-reject filter
4、How many crossover voltages does the open-loop comparator have? also how many crossover voltages does the schmitt trigger comparator have?
A、1，2
B、2，3
C、2，1
D、1，1
5、The circuit is shown in the figure. In order to make the circuit oscillate, the value of resistance R3 must be （ ） and the oscillation frequency of the circuit is （ ）.
A、>1.3k ohm，1kHz
B、>2.7k ohm，1kHz
C、<1.3k ohm，1kHz
D、<1.3k ohm，100Hz
E、>1.3k ohm，10kHz
F、>2.7k ohm，10kHz
6、The circuit is shown in the figure, the crossover voltage of the circuit must be ( ).
A、0V
B、+3V,-3V
C、+5V, -5V
D、+6V, -6V
7、The circuit is shown in the figure, the type of this filter is （ ）
A、Low-pass filter
B、High-pass filter
C、Band pass filter
D、Band-reject filter
8、For the circuit shown in Figure, the the R2/R1 required for oscillation is ( ).
A、R2/R1=1
B、R2/R1=2
C、R2/R1=3
D、R2/R1=0.5
9、Consider the Schmitt trigger in Figure, assume the saturated otput voltage are ±10V, find the VTH and VTL are ( ).
A、VTH=2V, VTL=-2V
B、VTH=2V, VTL=-4V
C、VTH=4V, VTL=-2V
D、VTH=4V, VTL=-4V
10、In the bridge rectifier, when the load resistor RL current is IL, then the average current for each diode ID is ( )
A、IL/2
B、IL
C、IL/4
D、2IL
11、In the circuit shown in the Figure, if we not consider the forward voltage drop on the diode, then the maximum reverse voltage of each diode is ( )
A、
B、
C、
D、
12、For the series regulator circuit, when the circuit is working normally, the regulating transistor is always in the ( ).
A、Forward active region
B、Switch
C、Cut-off
D、Unable to determine
13、For the circuit shown in Figure, the voltage for the node A is VA=( ).
A、20V
B、24V
C、28V
D、30V
14、For the circuit in Figure, the maximum value of the voltage on the load is ( ) ,and the minimum value is ( )
A、20V，9V
B、28V，9V
C、18V，9V
D、28V，18V
15、For the circuit in Figure, the voltage VA is ( ) and the voltage VB is ( )
A、-15V，+15V
B、+9V，-9V
C、-18V，+18V
D、+15V，-15V
16、The circuit is shown in the figure, the type of this filter is （ ）.
A、Low-pass filter
B、High-pass filter
C、Band-pass filter
D、Band-reject filter
17、If the frequency f-->0, the voltage gain of the circuit is equal the pass-band voltage gain, then the circuit may be ( ).
A、low-pass filter
B、high-pass filter
C、bandpass filter
D、band-reject filter
18、The circuit is shown in the figure, the type of this filter is （ ）.
A、Low-pass filter
B、High-pass filter
C、Band-pass filter
D、Band-reject filter
19、The circuit is shown in the figure,which voltage transfer characteristic is right( ).
A、
B、
C、
D、
20、Active filter circuit is usually composed of integrated operational amplifier, resistors and capacitors.
21、The cut-off frequency of low-pass filter must be lower than that of high-pass filter.
22、Under the condition of positive, if the phase shift of the feedback network if φβ, the phase shift of the amplifier circuit is φa, then the phase condition must be satisfied φβ+φa=(2n+1)π.
23、As long as the phase condition is satisfied, and |Aβ|>1, the oscillation can be produced.
24、In the amplifier circuit, as long as there is positive feedback, it will oscillate.
25、The circuit is shown in the figure,the phase condition of the oscillator is satisfied.
26、The circuit is shown in the figure,the phase condition of the oscillator is satisfied.
27、The oscillation condition of non sine wave oscillation circuit is the same as that of sine wave oscillation circuit.
28、Operational amplifiers for voltage comparators are always open-loop or positive feedback.
29、When selecting rectifier elements, only the dc voltage and DC current required for the load should be considered.
30、The average output voltage of full-wave rectifier circuit is doubled compared with that of half-wave rectifier.
31、In series regulator circuit, the transistor is in series with the load and operates in forward active region.
32、The circuit is shown in the figure,the lower corner frequency is （ ）rad/s.
Final examination questions of《Analog Electronics Technique》in autumn 2020
Final examination questions in autumn 2020
1、The power absorbed by the 2k ohm resistor in Figure is （ ）mW
A、9
B、4
C、2
D、1
2、For the circuit in Figure,the output voltage vo is ( )V.
A、3
B、-3
C、1
D、2
3、For the circuit in Figure,the output voltage vo is( ), and the output current io is ( )
A、100mV,25mA
B、250mV,25mA
C、350mV,25μA
D、450mV,25μA
4、For the circuit in the Figure, the op-amps are ideal, the input resistance is( )
A、Ri1=Ri2=1k ohm
B、Ri1<Ri2
C、Ri1>Ri2
D、Ri1=Ri2=∞
5、Determine the voltage transfer ratio vo/vs in this op-amp circuit, where R=10k ohm.
A、-1/3
B、-2/3
C、-1
D、-2
6、Assume all the Op-Amps are ideal, and when time t=0, the capacitor voltage vc=0, then when t=0, vo1=( ), vo2=( )
A、vo1=5V,vo2=1V;
B、vo1=-4V, vo2=-1V;
C、vo1=7V, vo2=1V;
D、vo1=5V, vo2=-1V
7、The circuit is shown as figure,the diodes are silicon diodes, and Vr=0.7V, the diodes D1 and D2 should be ( )
A、D1 on, D2 on;
B、D1 on, D2 off
C、D1 off, D2 off
D、D1 off,D2 on
8、For the circuit shown as figure, if we use ideal model, and the amplitude of the ac sine signal is 24V, then the peak current of the diode is( ), and the peak inverse voltage of the diode is ( ）
A、240mA，24V
B、120mA，12V
C、120mA，36V
D、360mA，36V
9、The circuit is shown as figure, the diode is silicon diode, and VDD = 2 V，R = 1kohm,vs=50sin(2pi*50t)mV，and Vγ=0.7V, then the quiescent current of the diode is ( ), the quiescent voltage of the output vO is ( ) , and the ac voltage amplitude of the output is ( )
A、2mA，2V；0.05V
B、1.3mA，1.3V；0.05V
C、2mA，2V；0.049V
D、1.3mA，1.3V；0.049V
10、The zener diode circuit is shown as figure, if VI =10V，R =100ohm，VZ =5V，IZ(min)=5mA，IZ(max)=50mA,Then the reisitance of RL should be ( )
A、>111 ohm
B、<111ohm
C、>111 kohm
D、<111k ohm
11、The circuit is shown as figure, the input voltages are shown in the table, the output voltage should be ( )
A、a
B、b
C、c
D、d
12、In the circuit in Figure， VGSQ=（ ）V，ID=（ ）mA，VDS=( )V;
A、VGSQ=4V,IDQ=4mA,VDSQ=-2V;
B、VGSQ=4V,IDQ=1mA,VDSQ=7V;
C、VGSQ=3V,IDQ=1mA,VDSQ=6V;
D、VGSQ=3V,IDQ=1mA,VDSQ=2.5V;
13、Assuming that the capacitors in the circuit are very large and can be regarded as short circuit to AC signal, the small signal equivalent circuit is （ ）?
A、
B、
C、
D、
14、Assuming that the DC operating points of all the following amplifier circuits are normal, all of the capacitors to AC signal can be regarded as a short circuit, and which circuit has the lowest input resistance （ ）
A、
B、
C、
D、
E、
15、Assuming that the DC operating points of all the following amplifier circuits are normal, all of the capacitors to AC signal can be regarded as a short circuit, and which circuit has the lowest output resistance （ ）
A、
B、
C、
D、
16、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit. The gm of T1 is gm=1mS.Determine the voltage gain of the circuit Av=vo/vi=（ ）
A、3.3
B、-3.3
C、-10
D、-0.77
17、The circuit is as shown in the figure, and the capacitance in the passband can be regarded as a short circuit.Determine the voltage gain of the circuit Av=vo/vi=（）
A、-0.89
B、0.89
C、10
D、-10
18、When a BJT transistor is used as an amplifying device, the base-emitter junction is ( ) biased, and the base-collector junction is ( ) biased.
A、Forward，forward
B、Reverse, reverse
C、Forward, reverse
D、Reverse, forward
19、If the source resistance of the signal source is 1kohm，and when the amplifying
中国大学Analog Electronics Technique
中国大学Analog Electronics Technique被认为是中国最好的电子技术学科之一。Analog Electronics Technique主要关注电子学的模拟部分，包括信号处理、放大、过滤和电源设计等方面。这是电气工程和电子工程领域的基础学科。
教学内容
在中国大学Analog Electronics Technique课程中，学生将学习以下内容：
- 基础电子器件的特性和特征
- 放大电路的设计和分析
- 滤波器的设计和分析
- 模拟信号处理的概念和应用
- 模拟信号处理电路的设计和实现
- 电源设计和管理
在课程的最后，学生将完成一个模拟电子设计项目。通过这个项目，他们将学习如何从设计到实现一个完整的电子系统。
实验室工作
中国大学Analog Electronics Technique课程的另一个重要方面是实验室工作。学生将在实验室中学习如何使用各种仪器和设备，例如示波器、信号发生器和频谱分析仪，来设计、分析和测试各种模拟电子电路。
实验室工作是这个课程的重要部分，因为它能够帮助学生将理论知识应用到实践中，从而更好地理解和掌握所学知识。
就业机会
在中国，Analog Electronics Technique毕业生在电子和电气工程领域内有广泛的就业机会。他们可以在各种行业和公司中找到工作，包括：
- 半导体制造商
- 电力公司
- 通信公司
- 电子设备公司
- 医疗设备公司
Analog Electronics Technique毕业生通常担任的职位包括模拟电路设计师、测试工程师、应用工程师和系统工程师。这些职位需要掌握Analog Electronics Technique的核心知识和技能。
结论
中国大学Analog Electronics Technique是一门重要的电子技术学科，因为它是电气工程和电子工程领域的基础。该课程的学生将学习各种模拟电子设计的核心知识和技能，包括信号处理、放大、过滤和电源设计等方面。通过实验室工作，学生将能够将理论知识应用到实践中，并为未来的职业生涯做好准备。
