MLX90614ESF-AAB ETC2 [List of Unclassifed Manufacturers], MLX90614ESF-AAB Datasheet - Page 14

• Manufacturer Part Number: MLX90614ESF-AAB
• Description: Single and Dual Zone
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

8.4.2 Differences with the standard SMBus specification (reference [1])
There are eleven command protocols for standard SMBus interface. The MLX90614 supports only two of
them. Not supported commands are:
Supported commands are:
8.4.3 Detailed description
The PWM/SDA pin of MLX90614 can operate also as PWM output, depending on the EEPROM settings. If
PWM is enabled, after POR the PWM/SDA pin is directly configured as PWM output. The PWM mode can be
avoided and the pin can be restored to its Data function by a special command. That is why hereafter both
modes are treated separately.
8.4.3.1 Bus Protocol
After every 8 bits received by the SD an ACK/NACK takes place. When a MD initiates communication, it first
sends the address of the slave and only the SD which recognizes the address will ACK, the rest will remain
silent. In case the SD NACKs one of the bytes, the MD should stop the communication and repeat the
message. A NACK could be received after the PEC. This means that there is an error in the received
message and the MD should try sending the message again. The PEC calculation includes all bits except the
START, REPEATED START, STOP, ACK, and NACK bits. The PEC is a CRC-8 with polynomial
X8+X2+X1+1. The Most Significant Bit of every byte is transferred first.
3901090614
Rev 003
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Quick Command
Byte commands - Sent Byte, Receive Byte, Write Byte and Read Byte
Process Call
Block commands – Block Write and Write-Block Read Process Call
Read Word
Write Word
PEC
Rd
Wr
Sr
S
S
A
S
1
Slave Address
Repeated Start Condition
Read (bit value of 1)
Write (bit value of 0)
Start Condition
Acknowledge (this bit can be 0 for ACK and 1 for NACK)
Stop Condition
Packet Error Code
Master-to-Slave
Slave-to-Master
7
Figure 4: SMBus packet element key
Wr
1
Page 14 of 40
A
1
Data Byte
8
Infra Red Thermometer in TO-39
MLX90614 family
A
1
P
1
Single and Dual Zone
Data Sheet
03/Oct/2007