Datasheet

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I
2
CInterfaceTimingRequirements
SwitchingCharacteristics
ResetTimingRequirements
PCA9548A
8-CHANNELI
2
CSWITCH
WITHRESET
SCPS143C–OCTOBER2006–REVISEDJUNE2007
overrecommendedoperatingfree-airtemperaturerange(unlessotherwisenoted)(seeFigure9)
STANDARDMODEFASTMODE
I
2
CBUSI
2
CBUS
UNIT
MINMAXMINMAX
f
scl
I
2
Cclockfrequency01000400kHz
t
sch
I
2
Cclockhightime40.6µs
t
scl
I
2
Cclocklowtime4.71.3µs
t
sp
I
2
Cspiketime5050ns
t
sds
I
2
Cserial-datasetuptime250100ns
t
sdh
I
2
Cserial-dataholdtime0
(1)
0
(1)
µs
t
icr
I
2
Cinputrisetime100020+0.1C
b
(2)
300ns
t
icf
I
2
Cinputfalltime30020+0.1C
b
(2)
300ns
t
ocf
I
2
Coutput(SDn)falltime(10-pFto400-pFbus)30020+0.1C
b
(2)
300ns
t
buf
I
2
Cbusfreetimebetweenstopandstart4.71.3µs
t
sts
I
2
Cstartorrepeatedstartconditionsetup4.70.6µs
t
sth
I
2
Cstartorrepeatedstartconditionhold40.6µs
t
sps
I
2
Cstopconditionsetup40.6µs
t
vdL(Data)
Valid-datatime(hightolow)
(3)
SCLlowtoSDAoutputlowvalid11µs
t
vdH(Data)
Valid-datatime(lowtohigh)
(3)
SCLlowtoSDAoutputhighvalid0.60.6µs
ACKsignalfromSCLlow
t
vd(ack)
Valid-datatimeofACKcondition11µs
toSDAoutputlow
C
b
I
2
Cbuscapacitiveload400400pF
(1)Adeviceinternallymustprovideaholdtimeofatleast300nsfortheSDAsignal(referredtotheV
IH
minoftheSCLsignal),tobridge
theundefinedregionofthefallingedgeofSCL.
(2)C
b
=totalbuscapacitanceofonebuslineinpF
(3)Datatakenusinga1-kΩpullupresistorand50-pFload(seeFigure10)
overrecommendedoperatingfree-airtemperaturerange,C
L
≤100pF(unlessotherwisenoted)(seeFigure9)
FROMTO
PARAMETERMINMAXUNIT
(INPUT)(OUTPUT)
R
ON
=20Ω,C
L
=15pF0.3
t
pd
(1)
PropagationdelaytimeSDAorSCLSDnorSCnns
R
ON
=20Ω,C
L
=50pF1
t
rst
(2)
RESETtime(SDAclear) RESET SDA500ns
(1)ThepropagationdelayisthecalculatedRCtimeconstantofthetypicalON-stateresistanceoftheswitchandthespecifiedload
capacitance,whendrivenbyanidealvoltagesource(zerooutputimpedance).
(2)t
rst
isthepropagationdelaymeasuredfromthetimetheRESETpinisfirstassertedlowtothetimetheSDApinisassertedhigh,
signalingastopcondition.Itmustbeaminimumoft
WL
.
overrecommendedoperatingfree-airtemperaturerange(unlessotherwisenoted)
PARAMETERMINMAXUNIT
t
W(L)
Pulseduration,RESETlow 6ns
t
REC(STA)
RecoverytimefromRESETtostart0ns
12
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