MLX90615 infrared thermometer and ESP32 example

The MLX90615 is a miniature infrared thermometer for non-contact temperature measurements. Both the IR sensitive thermopile detector chip and the signal conditioning ASIC are integrated in the same miniature TO-46 can.

The infrared 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 sensor achieves an accuracy of ±0.2°C within the relevant medical temperature range. The user can choose to configure the digital output to be PWM.

Features and benefits

Factory calibrated in wide temperature range: -20 to 85°C for sensor temperature and -40 to 115°C for object temperature
High accuracy of 0.5°C over wide temperature range (0..+50 C for both Ta and To)
Medical accuracy of 0.2°C in a limited temperature range
Measurement resolution of 0.02°C
SMBus compatible digital interface for fast temperature readings and building sensor networks
Customizable PWM output for continuous reading
3V supply voltage with power saving mode

Parts Required

Here are the parts I used

you can connect to the sensor using a standard header the classic dupont style jumper wire.

Name	Link
ESP32		Aliexpress link Amazon Ebay
MLX90615		Aliexpress link Ebay link Amazon Link
Connecting cables		Aliexpress link Amazon Ebay

Connection

esp32 and mlx90615

Code

This particular example comes from the following library which I installed – https://github.com/skiselev/MLX90615

I had issues with one of the other libraries – this one works just fine

#include <Wire.h>
#include <mlx90615.h>

MLX90615 mlx = MLX90615();

void setup() {
Serial.begin(9600);
Serial.println("Melexis MLX90615 infra-red temperature sensor test");
mlx.begin();
Serial.print("Sensor ID number = ");
Serial.println(mlx.get_id(), HEX);
}

void loop() {
Serial.print("Ambient = ");
Serial.print(mlx.get_ambient_temp());
Serial.print(" *C\tObject = ");
Serial.print(mlx.get_object_temp());
Serial.println(" *C");

Serial.println();
delay(500);
}

Output

Open the serial monitor and you should see something like this displayed

Ambient = 25.53 *C Object = 41.71 *C

Ambient = 25.61 *C Object = 42.53 *C

Ambient = 25.75 *C Object = 43.05 *C

Ambient = 25.79 *C Object = 35.17 *C

Ambient = 25.79 *C Object = 34.51 *C

Ambient = 25.79 *C Object = 34.39 *C

Ambient = 25.75 *C Object = 33.49 *C

Ambient = 25.75 *C Object = 32.81 *C

Links

https://www.melexis.com/-/media/files/documents/datasheets/mlx90615-datasheet-melexis.pdf