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V
BAT
V
输出
bq24030,bq24031,bq24032,
bq24032a,bq24035,bq24038,bq24039
SLUS618C–AUGUST2004–REVISEDJUNE2005
Figure12illustrateswhenabatteryisinsertedforpowerup;channel1(ch1)vac=0v;channel2(ch2)v
USB
=0v;channel3(ch3)v
输出
;outputcurrent,i
输出
=0.25aforv
输出
>2v;channel4(ch4)v
BAT
=3.5v;c
(dppm)
=0pf.whentherearenopowersourcesandthebatteryisinserted,theoutputtracksthebatteryvoltageif
thereisnoload(<10maofload)ontheoutput,asshown.ifaloadispresentthatkeepstheoutputmorethan
200mvbelowthebattery,ashort-circuitconditionisdeclared.atthistime,theloadhastoberemovedto
recover.acapacitorcanbeplacedonthedppmpintodelayimplementingtheshort-circuitmodeandget
unrestricted(notlimited)电流.
figure12.insertbattery–power-upoutputviabat
Figure13illustratesusbbootupandpower-upviausb;channel1(ch1)v
(ush)
=0to5v;channel2(ch2)
usbinputcurrent(0.2a/div);psel=低;ce=高;iset2=high;v
BAT
=3.85v;v
(dppm)
=3.0v(v
(dppm)
×
1.15<v
BAT
,otherwisedppmmodeincreasestimeduration).whenausbsourceisapplied(ifacisnot
呈现),thecepinandiset2pinareignoredduringtheboot-uptimeandamaximuminputcurrentof100ma
ismadeavailabletotheoutorbatpins.aftertheboot-uptime,theicimplementstheceandiset2pinsas
编写程序.
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