pca9538d NXP Semiconductors, pca9538d Datasheet - Page 6

• Manufacturer Part Number: pca9538d
• Description: 8-bit I2c And Smbus Low Power I/o Port With Interrupt And Reset
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Device address
Bus transactions
Data is transmitted to the PCA9538 registers using the write mode as shown in Figures 6 and 7. Data is read from the PCA9538 registers using
the read mode as shown in Figures 8 and 9. These devices do not implement an auto-increment function so once a command byte has been
sent, the register which was addressed will continue to be accessed by reads until a new command byte has been sent.
2006 Sep 21
8-bit I
I/O port with interrupt and reset
FROM PORT
REGISTER
DATA OUT
WRITE TO
DATA TO
SDA
SCL
PORT
SDA
2
SCL
C-bus and SMBus low power
start condition
start condition
S
S
Figure 5. PCA9538 address
1
1
1
1
1
1
FIXED
2
2
1
1
SLAVE ADDRESS
1
3
3
1
1
slave address
slave address
0
4
4
0
0
0
HARDWARE SELECTABLE
5
0
5
0
Figure 7. WRITE to configuration or polarity inversion registers
A1 A0
6
A1 A0
6
A1 A0
7
7
R/W
R/W
R/W
SW02175
0
0
8
8
Figure 6. WRITE to output port register
A
A
acknowledge
from slave
9
acknowledge
from slave
9
0
0
0
0
0
0
command byte
command byte
0
0
6
0
0
0
0
1
0
1/0
1
A
A
acknowledge
from slave
acknowledge
from slave
data to port
data to register
DATA
DATA 1
t
pv
PCA9538
Product data sheet
A
A
acknowledge
from slave
acknowledge
from slave
DATA 1 VALID
SW02177
P
P
SW02176