EVB90615 Melexis Inc, EVB90615 Datasheet - Page 12

• Manufacturer Part Number: EVB90615
• Description: EVAL BOARD FOR MLX90615
• Manufacturer: Melexis Inc

Specifications of EVB90615

• Sensor Type: Temperature
• Sensing Range: -40°C ~ 85°C
• Interface: SMBus (2-Wire/I²C)
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MLX90615
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Voltage - Supply: -
• Sensitivity: -
• Other names: Q4435148

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. If 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 transmitted first.
8.4.3.1.1 Read Word (depending on the command – RAM or EEPROM)
3901090615
Rev 001
S
………..
1
PEC
Slave Address
Rd
Wr
Sr
S
S
A
P
1
Slave Address
7
Data Byte Low
Start Condition
Repeated Start Condition
Read (bit value of 1)
Write (bit value of 0)
Acknowledge (this bit can be 0 for ACK and 1 for NACK)
Stop Condition
Packet Error Code
Master-to-Slave
Slave-to-Master
7
8
Figure 5: SMBus packet element key
Figure 6: SMBus read word format
Wr
1
1
A
Wr
1
A
1
Page 12 of 30
A
1
Command
Data Byte High
8
Data Byte
8
8
1
A Sr
A
1
1
A
1
Infra Red Thermometer
Slave Address
P
1
PEC
MLX90615
7
8
Rd
A
1
1
Data Sheet
28/Aug/2008
A
P
1
1
………..