www.德州仪器.com
在
OC1
OC2
2
8
3
5
4
7
0.1
µ
F 10
µ
F
内部的
函数
OUT1
电源 供应
3.3 v
EN1
6
0.1
µ
F 10
µ
F
OUT2
内部的
函数
0.1
µ
F
10
µ
F
USB
控制
地
V
总线
D−
D+
TPS2062
EN2
地
1
usbpower-distributionrequirements
tps2061,tps2062,tps2063
tps2065,tps2066,tps2067
SLVS490B–DECEMBER2003–REVISEDDECEMBER2004
applicationinformation(持续)
figure28.高-powerbus-poweredfunction
usbcanbeimplementedinseveralways,和,regardlessofthetypeofusbdevicebeingdeveloped,一些
电源-distributionfeaturesmustbeimplemented.
•
hosts/sphsmust:
–current-limitdownstreamports
–ReportovercurrentconditionsonUSBV
总线
•
bphsmust:
–enable/disablepowertodownstreamports
–powerupat<100ma
–limitinrushcurrent(<44
Ω
and10µf)
•
functionsmust:
–Limitinrushcurrents
–powerupat<100ma
thefeaturesetofthetps206xallowsthemtomeeteachoftheserequirements.theintegratedcurrent-限制的
andovercurrentreportingisrequiredbyhostsandself-poweredhubs.thelogic-levelenableandcontrolledrise
timesmeettheneedofbothinputandoutputportsonbus-poweredhubs,aswellastheinputportsfor
总线-poweredfunctions(seefigure29).
20