www.德州仪器.com
V
USB
I
USB
BatteryTemperatureMonitoring
9
TS
bqTINYIII
LTF
HTF
+
电池
包装
PACK+
PACK−
NTC
温度
I
TS
V
LTF
V
HTF
RT1
RT2
UDG−04086
9
TS
bqTINYIII
LTF
HTF
+
电池
包装
PACK+
PACK−
NTC
I
TS
V
LTF
V
HTF
UDG−04085
batterypre-conditioning
bq24030,bq24031,bq24032,
bq24032a,bq24035,bq24038,bq24039
SLUS618C–AUGUST2004–REVISEDJUNE2005
figure13.usbboot-uppower-向上
thebqtiny-iiicontinuouslymonitorsbatterytemperaturebymeasuringthevoltagebetweenthetsandvss
管脚.aninternalcurrentsourceprovidesthebiasformost-common10k
Ω
负的-temperaturecoefficient
thermistors(ntc)(看Figure14).thedevicecomparesthevoltageonthetspinagainsttheinternalv
(ltf)
和
V
(htf)
thresholdstodetermineifchargingisallowed.onceatemperatureoutsidethev
(ltf)
andV
(htf)
门槛
isdetected,thedeviceimmediatelysuspendsthecharge.thedevicesuspendschargebyturningoffthepower
fetandholdingthetimervalue(i.e.,timersarenotreset).chargeisresumedwhenthetemperaturereturnsto
thenormalrange.theallowedtemperaturerangefor103at-typethermistoris0°cto45°c.不管怎样,theuser
mayincreasetherangebyaddingtwoexternalresistors.看Figure15.
figure14.tspinconfigurationfigure15.tspinthresholds
duringachargecycle,ifthebatteryvoltageisbelowthev
(lowv)
门槛,thebqtiny-iiiappliesaprecharge
电流,i
o(prechg)
,tothebattery.thisfeaturerevivesdeeplydischargedcells.theresistorconnectedbetween
theiset1andvss,r
设置
,determinestheprechargerate.thev
(prechg)
andK
(设置)
parametersarespecifiedin
thespecificationstable.notethatthisappliestobothacandusbcharging.
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