Datasheet

PCA9555_8 © NXP B.V. 2009. All rights reserved.
Product data sheet Rev. 08 — 22 October 2009 16 of 34
NXP Semiconductors
PCA9555
16-bit I
2
C-bus and SMBus I/O port with interrupt
8. Application design-in information
Device address configured as 0100 000xb for this example.
IO0_0, IO0_2, IO0_3 configured as outputs.
IO0_1, IO0_4, IO0_5 configured as inputs.
IO0_6, IO0_7, and IO1_0 to IO1_7 configured as inputs.
Fig 19. Typical application
PCA9555
IO0_0
IO0_1
SCL
SDA
V
DD
(5 V)
MASTER
CONTROLLER
SCL
SDA
INT
IO0_2
V
DD
A2
A1
A0
V
DD
GND
INT
10 kΩ
SUB-SYSTEM 1
(e.g., temp sensor)
IO0_3
INT
SUB-SYSTEM 2
(e.g., counter)
RESET
controlled
switch
(e.g., CBT device)
V
DD
A
B
ENABLE
SUB-SYSTEM 3
(e.g., alarm system)
ALARM
IO0_4
IO0_5
IO0_6
10 DIGIT
NUMERIC
KEYPAD
V
SS
002aac704
10 kΩ10 kΩ 2 kΩ
IO0_7
IO1_0
IO1_1
IO1_2
IO1_3
IO1_4
IO1_5
IO1_6
IO1_7