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1 oz. 铜
电源 平面
1 oz. 铜
地面 平面
2 oz. 铜 焊盘 垫子
和 25 热的 vias
热的 vias, 0,3 mm
直径, 1,5 mm 程度
− 最大 接合面 temperature − 125
T
JM
C
°
1
2
3
4
5
0.1 1 10 100
− 最大 电源 消耗 − w
P
D
铜 散热器 范围 − cm
2
T
一个
= 55
°
C
非 空气 流动
150 lfm
250 lfm
SOT223PowerDissipation
TPS726126
tps72615,tps72616
tps72618,tps72625
SLVS403F–MAY2002–REVISEDMAY2005
thermalinformation(持续)
figure21.ddpakthermalresistance
FromthedatainFigure22andrearrangingEquation4,themaximumpowerdissipationforadifferentground
planeareaandaspecificambienttemperaturecanbecomputed.
figure22.maximumpowerdissipationvscopperheatsinkarea
thesot223packageprovidesaneffectivemeansofmanagingpowerdissipationinsurfacemountapplications.
TheSOT223packagedimensionsareprovidedinthe
MechanicalData
sectionattheendofthedatasheet.这
additionofacopperplanedirectlyunderneaththeSOT223packageenhancesthethermalperformanceofthe
包装.
toillustrate,thetps72625inasot223packagewaschosen.forthisexample,theaverageinputvoltageis
3.3v,theoutputvoltageis2.5v,theaverageoutputcurrentis1a,theambienttemperature55°c,noairflowis
呈现,andtheoperatingenvironmentisthesameasdocumentedbelow.neglectingthequiescentcurrent,这
maximumaveragepoweris:
10