并联稳压器提高功率放大器的电流限制精度

摘要：代替通常的晶体管在功率放大器电路的分流稳压器（U1），提高了限流精度。

Maxim>AppNotes>CIRCUITPROTECTIONPOWER-SUPPLYCIRCUITSKeywords:shuntregulator,currentlimit,poweramplifier,adjustableshuntregulatorJul26,2006APPLICATIONNOTE3867ShuntRegulatorImprovesPA'sCurrent-LimitAccuracyAbstract:Substitutingashuntregulator(U1)fortheusualtransistorinthispower-amplifiercircuitimprovesthecurrent-limitaccuracy.Addingcurrent-limitingcircuitrytoanemitterfollowerprotectsboththepasstransistoranddownstreamcircuitryfromexcessivecurrentdamage.Theclassicwaytoimplementsuchcurrentlimitingistoaddaballastresistorbetweenthepasstransistor'semitterandthecircuitoutput,andthenmonitortheresistordropwithasmall-signaltransistor.SeeR4andQ2inthepoweramplifier(