Assignment. Voltage Amplifiers. • Characteristics of Vo
Added on - 21 Sep 2019
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AssignmentVoltage AmplifiersCharacteristics of Voltage amplifiersoThe input signal is the voltage signal and the output signal is also the voltagesignal.oThis is a VCVS device which is Voltage-controlled voltage source.oIt has high input impedance and low output impedanceAmplification Feedback topologyoIn this, the sampling is of Voltage and mixing is of series (series-shunt)topologyThe output voltage signal is sampled by the feedback network and thefeedback signal xfis a voltage signal which is mixed with the inputsignal voltage in series.Here the word “Series” is related to the connection at the input and thethe connection at the output is represented by the term “shunt” whichmeans parallel.oCharacteristics:This stabilizes the voltage gain.The series connection at the input gives higher input resistance.The shunt connection at the output gives lower output resistance.Current AmplifierCharacteristics of Current Amplifiers:oThe input and output signals are both current.oIt is a CCCS source which stands for Current-controlled current sourceoThis amplifier has low input impedanceoThis amplifier has high input impedanceAmplifier Feedback topologyoCurrent-sampling shunt-mixing (shunt-series) topologyThe output current is sampled by the feedback network and thefeedback current signal can be mixed with the source current inparallel.The term “Shunt” is related to the input connection and the term“series” is related to the output connection.Characteristics:oThis circuit stabilizes the current gain.
oIn this current amplifier circuit, the input port of the amplifier offers the lowinput resistance and the high output resistance.Transconductance AmplifierCharacteristics of a trans-conductance amplifier:oThe Input signal in this amplifier is a voltage signal and the output signal isthe current signal.oThis is a VCCS device which stands for Voltage-controlled current source.oThis amplifier provides high input impedance.oThis amplifier provides high output impedance.Feedback topologyoThis is series-series topology which means Current-sampling series-mixing.The output current is sampled by feedback network and the feedbacksignal xfis a voltage that can be mixed with the source voltage inseries.There the term “Series” is related to the connection at the input and theother “series” word is related to the connection at the output.Characteristics:oThis amplifier stabilizes the trans-conductance gainoThe trans-conductance amplifier gives high input resistance at the input postof the amplifier and high output resistance at the output port of the amplifier.
Transresistance AmplifierCharacteristics of trans-resistance amplifier:oThe input signal of a trans-resistance amplifier is a current signal and outputsignal is a voltage signal.oIt is a CCVS device which stands for Current-controlled voltage source.oThis amplifier has low input impedance and low output impedanceFeedback topologyoVoltage-sampling shunt-mixing (parallel-parallel) topologyThe output voltage signal is sampled by the feedback network and thefeedback signal xfis a current which can be mixed in parallel with thesource current.The term “Shunt” is related to the input connection and the term“shunt” is also related to the output connection.Characteristics:oThis amplifier stabilizes the trans-resistance gain.oThe input of the trans-resistance amplifier provides low input resistance andthe output provides low output resistance.Effect of Feedback on Amplifier PerformanceCharacteristicVoltage SeriesCurrent SeriesCurrent ShuntVoltage ShuntFeedback SignalVoltageVoltageCurrentCurrentSampled SignalVoltageCurrentCurrentVoltageFeedback Gain(B)Feedbackvoltage/outputvoltageFeedbackvoltage/outputcurrentFeedbackCurrent/InputCurrentFeedbackCurrent/OutputVoltageOpen Loop GainAv= Vo/ViGm=Io/ViAi=Io/IiRm=Vo/IiD1+BAv1+BGm1+BAi1+BRmAfAv/DGm/DAi/DRm/DRifRiDRiDRi/DRi/DRofRo/DRoDRoDRo/DNumerical Problem