Datasheet

PCA9518A_3 © NXP B.V. 2008. All rights reserved.
Product data sheet Rev. 03 — 3 December 2008 9 of 23
NXP Semiconductors
PCA9518A
Expandable 5-channel I
2
C-bus hub
It is important to note that any arbitration or clock stretching events on Bus 1 require that
the V
OL
of the devices on Bus 1 be 70 mV below the V
OL
of the PCA9518A (see V
OL
−V
ILc
in the Section 9 “Static characteristics”) to be recognized by the PCA9518A and then
transmitted to Bus 0.
Fig 6. Bus waveforms
Bus 0
V
OL
of master
SCL of
master
SDA of
master
9
th
clock cycle
t
stretch
V
OL
of PCA9518A
9
th
clock cycle
EXPSDA1
t
PHL1
EXPSDA2
t
PHL2
t
PLH2
t
PLH2
, t
PLH1
expansion
bus
EXPSCL1
EXPSCL2
SCL of
slave
SDA of
slave
Bus 1
t
PHL
t
PLH
Bus n
with n > 1
V
OL
of slave V
OL
of PCA9518A
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