Stabilize Your Transimpedance Amplifier

Abstract:Transimpedanceamplifiers(TIAs)arewidelyusedtotranslatethecurrentoutputofsensorslikephotodiode-to-voltagesignals,sincemanycircuitsandinstrumentscanonlyacceptvoltageinput.AnoperationalamplifierwithafeedbackresistorfromoutputtotheinvertinginputisthemoststraightforwardimplementationofsuchaTIA.However,eventhissimpleTIAcircuitrequirescarefultrade-offsamongnoisegain,offsetvoltage,bandwidth,andstability.ClearlystabilityinaTIAisessentialforgood,reliableperformance.Thisapplicationnoteexplainstheempiricalcalculationsforassessingstabilityandthenshowshowtofine-tunetheselectionofthefeedbackphase-compensationcapacitor.Maxim>DesignSupport>TechnicalDocuments>Tutorials>AmplifierandComparatorCircuits>APP5129Maxim>DesignSupport>TechnicalDocuments>Tutorials>Sensors>APP5129Keywords:TIA,transimpedanceamplifier,transimpedanceamp,photodiode,medicalinstrumentation,industrialcontrol,piezo-sensorinterface,TIAstability,feedbackcapacitance,phasecompensation,bodeplotFeb03,2012TUTORIAL5129StabilizeYourTransimpedanceAmplifierBy:AkshayBhat,SeniorStrategicApplicationsEngineerFeb03,2012Abstract:Transimpedanceamplifiers(TIAs)arewidelyusedtotranslatethecurrentoutputofsensorslikephotodiode-to-voltagesignals,sincema