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34828An amplifier has a gain-bandwidth product of 200 MHz.A feedback network is added that has a feedback factor（1 + βA） of 18.88.What is the gain-bandwidth product for the circuit with the added feedback network？（）

34829The output impedance of current-shunt feedback amplifier（）；the output impedance of its op-amp.

34830Calculate the voltage gain for voltage series feedback when the amplifier gain is A = -2000 and F = -1/50.（）

34831The feedback circuit connection shown here is（）.

34832The power that an amplifier delivers to a load is equal to the difference between the power that the circuit draws from the power supply and the power that the circuit dissipates.（）。

34833Power amplifiers are typically used to drive low impedance loads.（）。

34834The maximum theoretical efficiency of an RC-coupled class A amplifier is（）.

34835Crossover distortion in class B amplifiers is prevented by（）.

34836A class B amplifier（not push-pull）（）.

34837An active filter that provides a constant output for input signals above

34838A second order low-pass filter has a high-end roll-off of（）.

34839A summing integrator is an op-amp integrator that has（）.

34840If the input voltage is 0.25 V and the output is -2.5 V， the value of must be（）.

34841The bandwidth of an amplifier is（）.

34842When 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 output of the device is 10 V.What is the CMPR of the device？（）

34843The inverting and noninverting inputs to an op-amp are used to drive a（n）（）amplifier.

34844The operational amplifier will only slightly amplify signals（）.

34845Under difference-mode operation， the difference-mode voltage gain for this circuit is（）.

34846An amplifier has a midband power gain of 24，500.What is the value of the power gain in dB for the circuit？（）

34847Negative dB values represent（）.

34848If several identical stages of amplifiers， each having the exact same upper and lower cutoff frequencies， are connected in cascade， then the bandwidth of the resulting amplifier will（）.

34849The（）；FET amplifier has low input impedance， high output impedance， and high voltage gain.

34850The（）；amplifier has high input impedance， low output impedance， and low voltage gain.

34851The FET version of the BJT'；s common-emitter configuration is the（）circuit.

34852A JFET can be biased in several different ways.The common method（s） of biasing an n-channel JFET is（are）（）.

34853The primary difference between JFETs and depletion-type MOSFETs is（）.

34854Which of the following biasing circuits can be used with E-MOSFETs？（）

34855Generally， it is good design practice for linear amplifiers to have operating points that close to（）.

34856This graphical solution represents（）.

34857FETs usually（）.

34858In the family of FETs， you can expect to find（）.

34859The region of the JFET drain curve that lies between pinch-off and breakdown is called（）.

34860Shockley'；s equation defines the（）of the FET and are unaffected by the network in which the device is employeD.

34861The voltage gain of a very well-designed common collector amplifier configuration， using a pnp transistor， is（）.

34862A transistor amplifier has an input signal applied to its emitter terminal and an output signal taken from its collector terminal.The amplifier is a（n）（）.

34863Calculate the voltage gain for this circuit.（）

34864The transistor model replaces the（）；with the junction diode's ac resistance.

34865Given this configuration， determine the input impedance if VS = 40 mV， Rsense = 0.5 kΩ， and the input current is 20 μA.（）

34866Voltage-divider bias stability is（）.

34867The term quiescent means（）.

34868The difference between the resulting equations for a network in which an npn transistor has been replaced by a pnp transistor is（）.

34869Calculate the collector-emitter voltage for this emitter-stabilized circuit.（）；

34870When a BJT is biased in the cutoff region the collector-to-emitter voltage is typically equal to（）.

34871The condition where increase in bias current will not cause further increases in collector current is called（）.

34872BJTs are commonly used as（）.

34873When a BJT is operating in the active region， the voltage drop from the base to the emitter is approximately equal to the（）。

34874In the active region， the base-emitter junction（）.

34875The circuit shown here is a（）.

34876Which of the following circuits is used to eliminate a portion of a signal？（）.

34877The resistor voltage and resistor current in this circuit are（）.

34878What is the value of the voltage dropped across forward-biased silicon diodes that are connected in parallel with each other？（）.

34879When a p-n junction is reverse-biased， its junction resistance is（）.

34880The piecewise linear model， equivalent circuit of the diode consists of（）.

34881When a diode is doped with either a pentavalent or a trivalent impurity its resistance will（）.

34882The characteristic of an ideal diode are those of a switch that can conduct current（）；.

34883Which of the following is not a commonly used semiconductor material'？（）

34884测得某放大电路的输入正弦电压和电流的峰值分别为10mV和10μA，在负载电阻为2KΩ时，测得输出正弦电压信号的峰值为2V。试计算该放大电路的电流放大倍数（）

34885测得某放大电路的输入正弦电压和电流的峰值分别为10mV和10μA，在负载电阻为2KΩ时，测得输出正弦电压信号的峰值为2V。试计算该放大电路的电压放大倍数（）

34886由于放大电路对信号中不同频率产生的（）不同而产生的波形失真，称为相位失真

34887由于放大电路对含有多种频率信号的（）不同而产生的波形失真，称为幅度失真

34888放大电路对不同频率的正弦信号的稳态响应特性简称为（）

34889已知某放大电路的输出电阻为3KΩ，在接有4KΩ负载电阻时，测得输出电压为2V。在输入电压不变的条件，断开负载电阻，输出电压将上升到（）

34890某放大电路在接有2KΩ负载电阻时，测得输出电压为3V，在输入电压不变的情况下断开负载电阻，输出电压上升到7.5V，说明该放大电路的输出电阻为（）

34891某放大电路在负载开路时，测得输出电压为5V，在输入电压不变的情况下接入3KΩ的负载电阻，输出电压下降到3V，说明该放大电路的输出电阻为（）

34892一般而言，放大器的质量和价格与它的衡量参数和主要指标紧密相关。

34893在模拟电子系统里，一般而言，传感器的作用是把非电的物理量转换为电信号，传输给后面电子系统进行处理。

34894这门课强调的是定性分析，手动的定量分析为估算。

34895非线性元件，指的就是元件的参数会随着它两端的电压电流而变化。

34896线性元器件，指的就是元件的参数与通过它的电压和电流是无关的。

34897直流电源是一种将交流信号转换为直流信号的信号处理电路。

34898在OCL乙类功放电路中，若最大输出功率为1W，则电路中功放管的集电极最大功耗约0.2W。

34899小功率的共射放大电路最适宜做功率放大电路。

34900衡量功率放大电路的主要技术指标有（）。

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