Review on HiLetgo GY-906 MLX90614ESF Non-contact Infrared Temperature Sensor Module for Arduino: Accurate IIC I2C Serial Measurement by Joshua Albright

Summary: My GY-906 switching module with Melexis P/N MLX90614ESF-BAA-000-TU did exactly what it was supposed to do. However, two out of five stars were removed because (1) the seller did not provide a diagram (I've attached this review) and (2) the seller did not specifically list the full MLX90614ESF part number on the Revain sales page. WARNING: This module is BAA version MLX90614. Please make sure you can use a thermopile sensor with a 90 degree Wide Field of View (FoV) before purchasing! Otherwise go to the Melexis website and find another version of the MLX90614 part with a narrower field of view. Melexis specifies parts with a field of view of up to 5 degrees, but they get pricey. Full Review: I was sent a GY-906 switch module with a Melexis P/N MLX90614ESF-BAA-000-TU sensor. Specification for MLX90614ESF - BAD-000-TU: ambient temperature -40С-85С, object temperature -70С-380С, case TO-39-4, 3V Vdd, single thermopile (zone), field of view 90 degrees, shipped in tube from factory. On the back of the board is a tiny linear LDO voltage regulator and two associated input/output capacitors to ground. The voltage regulator is used to step down the voltage from 5V to 3.3V that this part of MLX90614ESF-BAA-000-TU uses for Vdd. There are also two 4.7kΩ SMBus/I2C resistors that pull up the SDA and SCL outputs to 3.3V. (Two 10kΩ resistors would be better in my opinion.) I'm attaching the (ugly) revised diagram of the GY-906 at Switch Module. I tested the module with the Arduino Nano and Adafruit MLX90614 driver. It works as advertised. There are more complex drivers for this part compared to the Adafruit driver. But I'm lazy. I would like the seller to display the full part number of the MLX90614 prominently on the Revain page before I buy this module, then I would spend more and buy a different version of the MLX90614 like the Digi-Key. (I later found out in a post-purchase Q&A that this is part of the BAA version.) The problem is that the 90 degree part of the MLX90614ESF-BAA-000-TU field of view is too wide on this module, to make it this thing really useful for me anyway. I can significantly reduce my field of view by attaching a long tube to the end of the sensor. The problem is that the inside of the tube must have a very low emissivity mirror coating (e.g. PVD/CVD) otherwise you are (mostly) measuring the temperature inside the tube, not the target. Obviously, after adding the tubing, a recalibration lookup table needs to be created. But where can I get such a tube from? Melexis produces versions of this part with lower field of view specifications, such as down to 5 degrees. However, expect to pay around $50 for the best 5 degree piece in the crowd. Digi-Key sells them.