MLX90614 is a non-contact infrared (IR) temperature sensor made by Melexis. It measures the temperature of an object by detecting the infrared radiation it emits, so it does not need to touch the object.
VCC:Power (3.3V–5V depending on module)
GND:Ground
SDA:I²C Data
SCL:I²C Clock
Non-contact temperature measurement
Measures both:
Object temperature (the target you're pointing at)
Ambient temperature (the sensor's own surrounding temperature)
Temperature range:
Object: approximately -70°C to +380°C
Ambient: -40°C to +125°C
Resolution: 0.02°C
Communication interface: I²C/SMBus (most common) and PWM output on some versions.