Amplifier,Unit15,放大器,Amplifier,operationalamplifier,pulseamplifier,currentamplifier,voltageamplifier,Amplifier,Anamplifierincreasesthemagnitudeof,oramplifiers,anelectricsignal.Thesignalmaybederived,forexample,fromaTVantenna.Ofallcomponents,theamplifierisbyfarthemostwidelyusedbuildingblockinelectronicssystems.AnamplifiermayberepresentedbysimpleblockdiagramofFig.15-1.TheinputsignalvoltageisdenotedbyEsandtheinputsignalcurrentisdenotedbyIs.AcrosstheoutputterminalsisloadresistorRL.ResistanceRLmayre