Harman Kardon HK 990/230, Service Manual

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Philips Semiconductors Product data sheet
PCA9555 16-bit I
2
C and SMBus I/O port with interrupt
2004 Sep 30
BLOCK DIAGRAM
POWER-ON
RESET
INPUT
FILTER
I
2
C/SMBUS
CONTROL
INPUT/
OUTPUT
PORTS
WRITE pulse
READ pulse
A0
A1
A2
SCL
SDA
V
DD
V
SS
8-BIT
I/O0.0
I/O0.1
I/O0.2
I/O0.3
I/O0.4
I/O0.5
I/O0.6
I/O0.7
SU01439
NOTE: ALL I/Os ARE SET TO INPUTS AT RESET
V
INT
INT
8-BIT
INPUT/
OUTPUT
PORTS
I/O1.0
I/O1.1
I/O1.2
I/O1.3
I/O1.4
I/O1.5
I/O1.6
I/O1.7
WRITE pulse
READ pulse
LP FILTER
PCA9555
Figure 3. Block diagram
7 5