User Manual

Application Note
SMBus communication with MLX90614
390119061402 Page 28 of 32 Jan-2008
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Vdd,V (3V vers ion)
VinL, VinH, V
Vin,L,-40 °C,min
Vin,L,-40 °C,max
Vin,L,+2 7°C,m in
Vin,L,+2 7°C,m ax
Vin,L,+1 25 °C,min
Vin,L,+1 25 °C,max
Vin,H,-40°C,min
Vin,H,-40°C,max
Vin,H,+27°C,min
Vin,H,+27°C,max
Vin,H,+125°C,m in
Vin,H,+125°C,m ax
Fig.15: Input voltage levels versus power supply voltage and temperature
Both temperature and supply voltage increase both low and high thresholds.
9 Conclusion
The MLX90614 can easily be used in with the SMBus interface to build a network of sensors.
Also for a single sensor the SMBus interface can be the preferred choice for communicating with
the application controller.
In APPENDIX there are C functions which can be used to implement all SMBus transaction
formats to communicate with MLX90614. Because software implementation of the SMBus is
used, it is easy to adapt these functions for different microcontrollers.