电路原理课件讲义英文版 Chapter_5.ppt

IfAissuccessinlife thenAequalsXplusYplusZ WorkisX YisplayandZiskeepingyourmouthshut AlbertEinstein Chapter5OperationalAmplifiers 5 1Introduction5 2OperationalAmplifiers5 3IdealOpAmp5 4InvertingAmplifier5 5NoninvertingAmplifier5 6SummingAmplifier5 7DifferenceAmplifier5 8CascadedOpAmpCircuits 5 1Introduction OperationalAmplifier OpAmp运算放大器 activecircuitelement 有源电路元件 electronicunitthatbehaveslikeavoltage controlledvoltagesourcealsovoltageorcurrent controlledcurrentsource Function mathematicaloperations 数学运算 sum加 amplify乘 integrate积分 differentiate微分 Advantages versatile inexpensive easytouse funtoworkwith Usages inverter逆变器 voltagefollower电压跟随器 summer加法器 differenceamplifier差分放大器 5 2OperationalAmplifiers OpAmpanactivecircuitelement有源电路元件designedtoperformmathematicaloperationsofaddition加 subtraction减 multiplication乘 division除 differentiation微分 andintegration积分 anelectronicdevice电子设备consistingofacomplexarrangementofresistors transistors capacitors anddiodes二极管 acircuitbuildingblock电路组件availableinintegratedcircuitpackages集成电路块inseveralforms Typicalopamppackage a pinconfiguration指针配置 b circuitsymbol电路符号 Poweredopamp Equivalentcircuitmodel WhereA open loopvoltagegain开环电压增益Ri inputresistanceR0 outputresistance Typicalrangesforopampparameters ParameterTypicalrangeIdealvaluesOpen loopgain A105to108Inputresistance Ri106to1013Outputresistance R010to100Supplyvoltage Vcc5to24V Feedback Anegativefeedbackisachievedwhentheoutputisfedbacktotheinvertingterminaloftheopamp Closed loopgain theratiooftheoutputvoltagetotheinputvoltageswhenthereisafeedbackpathfromoutputtoinputOpamparegenerallyusedincircuitswithfeedbackpaths Threemodesofopampoperationregion Positivesaturation正饱和 v0 VccLinearregion Vcc v0 Avd VccNegativesaturation负饱和 v0 Vcc Example1 Theequivalentcircuit Findtheclosed loopgainv0 vs Determinecurrentiwhenvs 2V Solution Atnode1 Atnode0 Butvd v1 andA 2 105 Then Assignment Readsection5 1and5 2inpages166 168TranslateEnhancingyourcareerinpage165 Vocabulary measurement测量paramount极为重要的proliferate激增ammeter安培表voltmeter电压表ohmmeter欧姆表oscilloscope示波器spectrumanalysis谱分析仪signalgenerator信号发生器patent申请专利specialist专家 5 3IdealOpAmp IdealOpAmp 理想运算放大器 Infiniteopen loopgain A Infiniteinputresistance Ri Zerooutputresistance R0 0 Twoimportantcharacteristicsi1 0 i2 0vd v2 v1 0orv1 v2 Example2 AccordingtothecharacteristicsofIdealopamp Solution So Atnode0 Calculatetheclosed loopgainv0 vs Findi0whenvs 1V Keepinmind Throughoutthisbook weassumethateveryopampisideal Throughoutthisbook weassumethatopampoperatesinthelinearrange 5 4InvertingAmplifier Atnode1 Butv1 v2 0foranidealopamp hence Voltagegain Equivalentcircuitfortheinverter Aninvertingamplifierreversesthepolarityoftheinputsignalwhileamplifyingit Assignment Solvetheproblems5 7 5 10and5 17inpages191 193 5 4NoninvertingAmplifier Atnode1 Butv1 v2 vi hence Voltagegain VoltageFollower UnityGainAmplifier Merits Highinputimpedance高输入阻抗Function IsolatetwocascadedstagesofacircuitUsage Intermediate stage orbuffer amplifier VoltageFollower Example3 Calculatetheoutputvoltagev0 Solution1 Usingsuperposition Wherev01 the6 Vvoltagesourcev02 the4 Vvoltagesource 1 Togetv01 thecircuitisaninverter 2 Togetv02 thecircuitisannoninvertingamplifier 3 Thus Solution2 Nodalanalysis Butva vb 4 andso Atnodea 5 5SummingAmplifier Atnodea But Asummingamplifierisanopampcircuitthatcombinesseveralinputsandproducesanoutputthatistheweightedsumoftheinputs 5 5DifferenceAmplifier Atnodea Atnodeb But Subt