www.德州仪器.com
usinglow-esrcapacitors
bridged-tiedloadvssingle-endedload
电源
V
(rms)
2
R
L
V
(rms)
V
o(pp)
2 2
(5)
R
L
2x v
o(pp)
V
o(pp)
-v
o(pp)
V
DD
V
DD
TPA6011A4
SLOS392A–FEBRUARY2002–REVISEDJULY2004
astable4indicates,mostofthebassresponseisattenuatedintoa4-
Ω
加载,an8-
Ω
loadisadequate,
headphoneresponseisgood,anddriveintolinelevelinputs(ahomestereoforexample)isexceptional.
低-esrcapacitorsarerecommendedthroughoutthisapplicationssection.areal(asopposedtoideal)
capacitorcanbemodeledsimplyasaresistorinserieswithanidealcapacitor.thevoltagedropacrossthis
resistorminimizesthebeneficialeffectsofthecapacitorinthecircuit.thelowertheequivalentvalueofthis
阻抗,themoretherealcapacitorbehaveslikeanidealcapacitor.
figure36showsaclass-abaudiopoweramplifier(apa)inabtlconfiguration.thetpa6011a4btlamplifier
consistsoftwoclass-abamplifiersdrivingbothendsoftheload.thereareseveralpotentialbenefitstothis
differentialdriveconfiguration,但是,initiallyconsiderpowertotheload.thedifferentialdrivetothespeaker
meansthatasonesideisslewingup,theothersideisslewingdown,andviceversa.thisineffectdoublesthe
voltageswingontheloadascomparedtoagroundreferencedload.plugging2
×
V
o(pp)
intothepowerequation,
wherevoltageissquared,yields4
×
theoutputpowerfromthesamesupplyrailandloadimpedance(看
equation5).
figure36.桥-tiedloadconfiguration
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