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bq24039Differences
bq24038Differences
autonomouspowersourceselection,pselcontrolpin
激励-upsequence
bq24030,bq24031,bq24032,
bq24032a,bq24035,bq24038,bq24039
SLUS618C–AUGUST2004–REVISEDJUNE2005
functionaldescriptions(持续)
thebq24039operatesdifferentlyfromothercorepartswhendealingwithpsel,usbchargelevels,andcharge
terminationlevels.pin8ischangedfropseltoiset3.不管怎样,thepselfunctionwastiedhighinternally,
makingtheinputacadaptorthefirstchoicewhenpresent.whenacispresent,thepselpinisnotexternally
availabletotransfertotheusbinput(togglepsellow).
theiset3pin,whensethigh,canbethoughtofasa2xmultiplierfortheiset2currentprogramlevel(usb
100/500ma->200/1000ma).theiset3alsoprogramstheterminationleveltoc/10whensethighandc/25
whensetlow,forallchargingsources.
thebq24038replacesusbpgwithpinvbsel,toenableuserselectionofthechargevoltage.inaddition,管脚
acpgwasmodifiedtopg.pgisactivelowwheneitheracpowerorusbpowerisdetected.
thepselpinselectsthepriorityoftheinputsources(高=交流,低=usb),ifthatprimarysourceisnot
有(basedonacpg,usbpgsignal),thenitusesthesecondarysource.ifneitherinputsourceis
有,thenthebatteryisselectedasthesource.withthepselinputhigh,thebqtiny-iiiattemptstocharge
fromtheacinput.ifacinputisnotpresent,theusbisselected.ifbothinputsareavailable,theacadapter
haspriority.withthepselinputlow,thebqtiny-iiidefaultstousbcharging.ifusbinputisgrounded,thenthe
bqtiny-iiichargesfromtheacinputattheusbchargerate(asselectedbyiset2).thisfeaturecanbeusedin
systemwhereacandusbpowersourceselectionisdoneelsewhere.thepselfunctionissummarizedin
Table1.
table1.powersourceselectionfunctionsummary
(1)
pselstateacusbchargemaximumsystemusbboot-向上
SOURCECHARGERATE
(2)
POWERFEATURE
源
呈现
(3)
AbsentACISET2ACEnabled
Absent
(4)
PresentUSBISET2USBEnabled
低
PresentPresentUSBISET2USBEnabled
absentabsentn/一个/abatterydisabled
PresentAbsentACISET1ACDisabled
AbsentPresentUSBISET2USBDisabled
高
PresentPresentACISET1ACDisabled
absentabsentn/一个/abatterydisabled
(1)table1isforallicswiththefollowingexception:forbq24039,thepselistiedhighinternallyandiset3determinesifbootupis
使能(iset3=低=使能;iset3=高=无能).
(2)batterychargerateisalwayssetbyiset1,butmaybereducedbyalimitedinputsource(iset2usbmode)andi
输出
systemload.
(3)
呈现
isdefinedasinputbeingatahighervoltagethanthebatvoltage(sourcespowergoodislow).
(4)
ACAbsent
isdefinedasacinputnotpresent(acpgishigh)orq1turnedoffduetoovervoltageinbq24035/39.
inordertofacilitatethesystemstart-upandusbenumeration,thebqtiny-iiioffersaproprietaryboot-向上
sequence.onthefirstapplicationofpowertothebqtiny-iii,thisfeatureenablesthe100-mausbchargerate
foraperiodofapproximately150ms,(t
(激励-向上)
),ignoringtheiset2andceinputssetting.attheendofthis
时期,thebqtiny-iiiimplementsceandiset2inputssettings.Table1indicateswhenthisfeatureisenabled.
看Figure13.
13
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