Datasheet

www.ti.com
A
A
A
A
S 0 1 1 1 A1A2 A0 1
Data 1 1 PData 3
Start
Condition
Acknowledge
From Slave
Acknowledge
From Slave
Data From Port Data From PortSlave Address
R/W
87654321
t
ir
t
ir
t
sps
t
iv
Data 1 Data 2 Data 3
INT
Data
Into
Port
B
B
A
A
P
n
INT
R/W A
t
ir
0.7 × V
CC
0.3 × V
CC
0.7 × V
CC
0.3 × V
CC
0.7 × V
CC
0.3 × V
CC
0.7 × V
CC
0.3 × V
CC
SCL
View B−BView A−A
t
iv
INT
W A
0.7 × V
CC
0.3 × V
CC
SCL
D
t
pv
Slave
Acknowledge
Unstable
Data
Last Stable Bit
SDA
P
n
PCF8574A
REMOTE 8-BIT I/O EXPANDER FOR I
2
C BUS
SCPS069D – JULY 2001 – REVISED OCTOBER 2005
PARAMETER MEASUREMENT INFORMATION (continued)
Figure 2. Interrupt Voltage Waveforms
Figure 3. I
2
C Write Voltage Waveforms
8