www.德州仪器.com
VC1
VC2
VC4
VC3
地
VDD
输出
CD
1.2 v (典型值)
R
V
D
C
V
D
I
C
D
= 0.2
一个 (典型值)
C
I
N
R
I
N
R
I
N
R
I
N
R
I
N
C
I
N
C
I
N
C
I
N
C
(延迟)
OVERVOLTAGEPROTECTION
DELAYTIMECALCULATION
t
d
1.2 V
C
(延迟)
I
CD
C
(延迟)
t
d
I
CD
1.2 V
bq29410,bq29411,bq29412
SLUS669B–AUGUST2005–REVISEDDECEMBER2005
FUNCTIONALBLOCKDIAGRAM
WhenoneofthecellvoltagesexceedsV
(保护)
,aninternalcurrentsourcebeginstochargethecapacitor,
C
(延迟)
,connectedtothecdpin.ifthevoltageatthecdpin,v
cd,
reaches1.2v,theoutpinisactivatedand
transitionshigh.anexternallyconnectednchfetisactiviatedandblowstheexternalfuseinthepositive
batteryrail;seethefunctionalblockdiagram.
IfallcellvoltagesfallbelowV
(保护)
beforethevoltageatpincdreaches1.2v,thedelaytimedoesnotrun
输出.aninternalswitchclampsthecdpintogndanddischargesthecapacitor,c
(延迟)
,andsecuresthefull
delaytimeforthenextoccurringovervoltageevent.
oncethepinoutisactivated,ittransitionsbackfromhightolowafterallbatterycellsreachv
(保护)
–V
hys.
thedelaytimeiscalculatedasfollows:
WhereI
(cd)
=cdcurrentsource=0.18µa
5
: 点此下载
