山东建筑大学试卷FX共5页第1页2006至2007学年第二学期课程名称模拟电子技术(本科)试卷A专业:电气工程与自动化、电子信息工程、通信工程试卷性质:闭卷考试时间120分钟题号一二三四五六总分分数得分阅卷人一、选择正确答案填入空内(用A、B、C、D填入即可)。(每空1分、共15分)1、二极管的主要特性是。A.放大特性B.恒温特性C.单向导电特性D.恒流特性2、稳压管的稳压区是其工作在。A.正向导通B.反向截止C.反向击穿3、在晶体管放大电路中,测得晶体管的各个电极的电位如图1所示,该晶体管的类型是。A.NPN型硅管B.PNP型硅管C.NPN型锗管D.PNP型锗管2V6V1.3V图14、在放大电路中,场效应管应工作在漏极特性的。A.可变电阻区B.恒流区C.截止区D.击穿区5、当晶体管工作在放大区时,发射结电压和集电结电压应为。A.前者反偏、后者也反偏B.前者正偏、后者反偏C.前者正偏、后者也正偏6、在由NPN晶体管组成的基本共射放大电路中,当输入信号为1kHz、5mV的正弦电压时,输出电压波形出现了底部削平的失真,这种失真是。A.饱和失真B.截止失真C.交越失真D.频率失真7、当我们想要放大频率为10kHz以上的信号时,应采用。A.低通滤波器B.高通滤波器C.带阻滤波器D.带通滤波器8、要使放大器的输入电阻提高,输出电阻减小,该放大器应引入。A.电流串联负反馈B.电压并联负反馈C.电流并联负反馈D.电压串联负反馈9、放大器的增益是随着输入信号频率的改变而改变的,当输入信号的频率为Hf时,放大器增益的幅值将。A.降为1B.降为中频时的1/2倍C.降为中频时的2/1倍D.降为中频时的2倍10、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为。A.1WB.0.5WC.0.2W11、制作频率为2MHz~20MHz的接收机的本机振荡器,应选用。A.RC桥式正弦波振荡电路B.LC正弦波振荡电路C.石英晶体正弦波振荡电路12、在RC桥式正弦波振荡电路中,当满足相位起振条件时,则其中电压放大电路的放大倍数必须满足才能起振。A.AV=1B.AV=3C.AV<3D.AV>313、选用差分放大电路的原因是。A.克服温漂B.提高输入电阻C.稳定放大倍数D.输出电阻增大14、组合放大电路的输出级采用射极输出方式是为了。A.增大电压放大倍数B.减小输出电流C.增大输出电阻D.提高带负载能力15、直流稳压电源中滤波电路的目的是。A.将交流变为直流B.将高频变为低频C.将交、直流混合量中的交流成分滤掉班级:电气134姓名房鑫学号20130811106山东建筑大学试卷FX共5页第2页二、分析题(本题共30分,每小题6分)1、电路如图2所示,已知ui=5sinωt(V),试画出ui与uO的波形,并标出幅值。设二极管是理想的。2、试分别画出图3所示各电路的电压传输特性。得分阅卷人3、电路如图4所示。(1)为使电路产生正弦波振荡,标出集成运放的“+”和“-”;并说明电路是哪种正弦波振荡电路。(2)若Rf短路,则电路将产生什么现象?(3)若Rf断路,则电路将产生什么现象?4、试用相位平衡条件判断图5所示各电路是否可能产生正弦波振荡?为什么?···········································································································装订线··································································································图2图3图4图5山东建筑大学试卷FX共5页第3页5、电路如图6所示。合理连线,构成5V的直流电源。三、计算题(本题共15分)电路如下图所示,晶体管的=100,'bbr=100Ω。(1)求解电路的Q点;(2)求电压放大倍数uA、输入电阻Ri和输出电阻Ro;(3)若Rb2和Rb1分别断开时,问电路能否正常工作?简述理由。得分阅卷人···········································································································装订线··································································································图6图7山东建筑大学试卷FX共5页第4页四、计算题(共15分,其中第1题10分,第2题5分)1、已知图8所示电路中的集成运放均为理想运放,试求解电路的运算关系。2、图9所示为恒流源电路,已知稳压管工作在稳压状态,试求负载电阻中的电流IL。得分阅卷人五、分析题(共10分)已知电路如图10所示,T1和T2管的饱和管压降│UCES│=3V,VCC=15V,RL=8Ω。选择正确答案填入空内。(1)电路中D1和D2管的作用是消除。A.饱和失真B.截止失真C.交越失真(2)静态时,晶体管发射极电位UEQ。A.>0VB.=0VC.<0V(3)最大输出功率POM。A.≈28WB.=18WC.=9W(4)当输入为正弦波时,若R1虚焊,即开路,则输出电压。A.为正弦波B.仅有正半波C.仅有负半波(5)若D1虚焊,则T1管。A.可能因功耗过大烧坏B.始终饱和C.始终截止得分阅卷人图8图10图9···········································································································装订线··································································································山东建筑大学试卷FX共5页第5页六、(本题共15分)由差动放大器和运算放大器组成的反馈放大电路如图11所示,试回答下列问题:1、当Ui=0时,UC1=?UC2=?设UBE=0.7V。2、要使由UO到b2的反馈为电压串联负反馈,则C1和C2应分别接至运放的哪个输入端(在图中用+、-号标出)?3、引入电压串联负反馈对电路性能有何影响(稳定输出电压还是输出电流,输入、输出电阻有何变化)?在深度负反馈下的闭环电压放大倍数Auf是多少?设A是理想运放。4、若要引电压并联负反馈,则C1、C2又应分别接到运放的哪个输入端?Rf应接到何处?若Rf、Rb数值不变,则Auf=?得分阅卷人图11···········································································································装订线··································································································