Harman Kardon HK 990/230 Service Manual page 77

Philips Semiconductors
2
16-bit I C and SMBus I/O port with interrupt
BLOCK DIAGRAM
PCA9555
A0
A1
A2
SCL
SDA
V
DD
V
SS
2004 Sep 30
2
I C/SMBUS
CONTROL
INPUT
FILTER
POWER-ON
RESET
Figure 3. Block diagram
75
INPUT/
8-BIT
OUTPUT
PORTS
WRITE pulse
READ pulse
INPUT/
8-BIT
OUTPUT
PORTS
WRITE pulse
READ pulse
LP FILTER
NOTE: ALL I/Os ARE SET TO INPUTS AT RESET
Product data sheet
PCA9555
I/O1.0
I/O1.1
I/O1.2
I/O1.3
I/O1.4
I/O1.5
I/O1.6
I/O1.7
I/O0.0
I/O0.1
I/O0.2
I/O0.3
I/O0.4
I/O0.5
I/O0.6
I/O0.7
V
INT
INT
SU01439