MAX7318AWG-T Maxim Integrated, MAX7318AWG-T Datasheet - Page 8

• Manufacturer Part Number: MAX7318AWG-T
• Description: Interface - I/O Expanders 16-Bit I/O Port Expander
• Manufacturer: Maxim Integrated
• Series: MAX7318r

Specifications of MAX7318AWG-T

• Maximum Operating Frequency: 400 KHz
• Operating Supply Voltage: 2 V to 5.5 V
• Operating Temperature Range: - 40 C to + 125 C
• Mounting Style: SMD/SMT
• Package / Case: SOIC-24 Wide
• Output Current: 43 mA
• Power Dissipation: 1667 mW

2-Wire-Interfaced, 16-Bit, I/O Port Expander
with Interrupt and Hot-Insertion Protection
generates the acknowledge bit since the MAX7318 is
the recipient. When the MAX7318 is transmitting to the
master, the master generates the acknowledge bit.
The MAX7318 has a 7-bit-long slave address (Figure 6).
The 8th bit following the 7-bit slave address is the R/W
bit. Set this bit low for a write command and high for a
read command.
Figure 6. Slave Address
Table 1. Command-Byte Register
Figure 7. Writes to Output Registers Through Write-Byte Protocol
8
_______________________________________________________________________________________
COMMAND BYTE
SDA
SDA
ADDRESS (hex)
MSB
A6
SDA
0x00
0x01
0x02
0x03
0x04
0x05
0x06
0x07
0xFF
SCL
CONDITION
START
WRITE TO PORT
DATA OUT PORT 1
READ FROM PORT 2
S
A5
1
2
A4
PROGRAMMABLE
SLAVE ADDRESS
3
4
A3
Input port 1
Input port 2
Output port 1
Output port 2
Port 1 polarity inversion
Port 2 polarity inversion
Port 1 configuration
Port 2 configuration
Factory reserved. (Do not write to this register.)
5
R/W
6
A2
7
ACKNOWLEDGE
8
FROM SLAVE
A1
9
A
LSB
0
A0
Slave Address
0
COMMAND BYTE
FUNCTION
R/W
0
0
ACK
0
0
1
ACKNOWLEDGE
FROM SLAVE
0 A
7
6
Slave address pins AD2, AD1, and AD0 choose 1 of 64
slave ID addresses (Table 7).
The command byte is the first byte to follow the 8-bit
device slave address during a write transmission
(Table 1, Figure 7). The command byte is used to deter-
mine which of the following registers are written or read.
Transmit data to the MAX7318 by sending the device
slave address and setting the LSB to a logic zero. The
command byte is sent after the address and deter-
mines which registers receive the data following the
command byte (Figure 7).
PORT 1 DATA
5
4
3
Read byte
Read byte
Read/write byte
Read/write byte
Read/write byte
Read/write byte
Read/write byte
Read/write byte
2
1
ACKNOWLEDGE
FROM SLAVE
0 A
PROTOCOL
7
—
t
PV
6
PORT 2 DATA
5
4
3
Data Bus Transaction
2
Writing to Port Registers
1
ACKNOWLEDGE
0
FROM SLAVE
A
POWER-UP
XXXX XXXX
XXXX XXXX
DEFAULT
1111 1111
1111 1111
0000 0000
0000 0000
1111 1111
1111 1111
t
PV
—