The MLX90614 is an Infra Red thermometer for non contact temperature measurements.. it mesures temparature by reading infrared rediation from surrounding objects. Both the IR sensitive thermopile detector chip and the signal conditioning ASIC are integrated in the same TO-39 package. A low noise amplifier, 17-bit ADC and powerful DSP units in MLX90614 are responcible for achieving high accuracy and resolution of the thermometer.
The thermometer comes factory calibrated with a digital SMBus output giving full access to the measured temperature in the complete temperature range(s) with a resolution of 0.02°C.
The user can configure the digital output to be pulse width modulation (PWM). As a standard, the 10-bit PWM is configured to continuously transmit the measured temperature in range of -20 to 120°C, with an output resolution of 0.14°C.
Data Sheet: http://melexis.com/Assets/IR-sensor-thermometer-MLX90614-Datasheet-5152.aspx