High-Efficiency Class D Audio Amplifiers Extend Battery Life in Portable Applica

Abstract:ThisapplicationnoteexaminestheoperationandbenefitsofaClassD(switch-modeandfilterless)audioamplifier.Switch-modeamplifierssuchasthemonoMAX4295andstereofilterlessMAX9701offerhighqualityaudiowithimprovedefficiencywhencomparedtotraditionallinearaudioamplifiers(ClassA,ClassB,andClassAB).ThisapplicationnotepresentsanoverviewoftraditionallinearaudioamplifierdesignsandthencomparesthemwithClassDamplifierdesign.ThebenefitsofnewerClassGamplifiersareacknowledged.ThearticleshowsefficiencycalculationsandoutputfilterdesignforClassDamplifiers.ThehighefficiencyofClassDamplifiersisdemonstratedwiththeMAX9701.Maxim>AppNotes>AmplifierandComparatorCircuitsAudioCircuitsKeywords:audioamplifier,speakerdriver,BTL,bridge-tiedload,switchingaudio,ClassD,PWM,switch-mode,H-bridge,efficiencySep20,2010APPLICATIONNOTE1760High-EfficiencyClassDAudioAmplifiersExtendBatteryLifeinPortableApplicationsAbstract:ThisapplicationnoteexaminestheoperationandbenefitsofaClassD(switch-modeandfilterless)audioamplifier.Switch-modeamplifierssuchasthemonoMAX4295andstereofilterlessMAX9701offerhighqualityaudiowithimprovedefficiencywhencomparedtotraditionallinearaudioamplifiers(ClassA,ClassB,andClassAB).ThisapplicationnotepresentsanoverviewoftraditionallinearaudioamplifierdesignsandthencomparesthemwithClassDampli