MAX31785ETL+ Maxim Integrated Products, MAX31785ETL+ Datasheet - Page 17

• Manufacturer Part Number: MAX31785ETL+
• Description: Board Mount Temperature Sensors 6Ch Intelligent Fan Controller
• Manufacturer: Maxim Integrated Products

Specifications of MAX31785ETL+

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The device supports the group command. With the
group command, a host can write different data to
multiple devices on the same serial bus with one long
The device responds to receiving its fixed slave address
by asserting an acknowledge (ACK) on the bus. The
device does not respond to a general call address; it
only responds when it receives its fixed slave address.
The only exception to this operation is if the ALERT
output is enabled (ALERT bit = 1 in MFR_MODE) and
ALERT has been asserted. When this condition occurs,
the device only recognizes the alert response address
(0001 100, 18h). See the ALERT and Alert Response
Address (ARA) section for more details.
If the ALERT output is enabled (ALERT bit = 1 in
MFR_MODE), when a fault occurs the device asserts the
ALERT signal and then waits for the host to send the alert
ALERT and Alert Response Address (ARA)
SLAVE ADDRESS, COMMAND BYTE, AND DATA WORD FOR DEVICE 1
SLAVE ADDRESS, COMMAND BYTE, AND DATA BYTE FOR DEVICE 2
SLAVE ADDRESS AND SEND BYTE FOR DEVICE 3
U U U
SLAVE ADDRESS, COMMAND BYTE, AND DATA WORD FOR DEVICE N
Sr
Sr
Sr
S
1
1
1
1
ADDRESS
ADDRESS
ADDRESS
ADDRESS
SLAVE
SLAVE
SLAVE
SLAVE
7
7
7
7
W
W
W
W
1
1
1
1
A
1
A
1
A
A
1
1
6-Channel Intelligent Fan Controller
COMMAND
COMMAND
COMMAND
COMMAND
Group Command
CODE
CODE
CODE
CODE
8
8
8
8
Addressing
A
1
A
A
A
1
1
1
DATA BYTE
DATA BYTE
DATA BYTE
LOW
LOW
U U U
8
8
8
continuous data stream. All the devices addressed dur-
ing this transaction wait for the host to issue a STOP
before beginning to respond to the command.
response address (ARA) as shown in the Alert Response
Address (ARA) Byte Format section. While waiting for
the ARA, the device does not respond to its fixed
slave address.
When the ARA is received and the device is asserting
ALERT, the device ACKs it and then attempts to place
its fixed slave address on the bus by arbitrating the
bus, since another device could also try to respond to
the ARA. The rules of arbitration state that the lowest
address device wins. If the device wins the arbitration,
it deasserts ALERT and begins to respond to its fixed
slave address. If the device loses arbitration, it keeps
ALERT asserted and waits for the host to once again
send the ARA.
A
1
1
A
A
1
DATA BYTE
DATA BYTE
HIGH
HIGH
U U U
8
8
KEY:
S = START
Sr = REPEATED START
P = STOP
W = WRITE BIT (0)
A = ACKNOWLEDGE (0)
SHADED BLOCK = SLAVE TRANSACTION
A
1
1
A
Group Command Write Format
1
P
U U U
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