I2C addresses of the most common sensors and actuators

9 February 2021
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I2C
10 minutes

To facilitate the development of your connected objects based on Arduino, ESP32, ESP8266, STM32 or Raspberry Pi micro-controllers, here is a list of the most common I2C (breakout) modules. Ambient sensors (temperature, relative humidity, atmospheric pressure, light intensity, etc.), detection of pollutants (CO, CO2, eTVOC, etc.), AMG8833 thermal camera, LDC2004 or SSD1306 screens and I/O expansion boards digital or analog.

Each manufacturer has provided a method to activate the alternative I2C address. Generally, it will be necessary to make a small solder on the module (breakout) or to apply a voltage (3V3 or 5V for example). On the other hand, it is very rarely possible to modify the address by programming.

Here are two examples that we meet quite often

BME280	BH1750FVI

To assign the i2c address 0x77, you have to solder a jumper between the two right pins and cut the track between the two left pins	To assign the address 0x5C, a voltage greater than 0.7V must be applied to the ADDR pin

To learn more about the I2C bus, you can continue by reading this article

Arduino, ESP32 or ESP8266 I2C scanner

If you can’t find your component’s I2C address or are having communication issues, here is the source code for an Arduino, ESP32, and ESP8266 compatible I2C scanner.

Note, the Wire.h library for ESP8266 and ESP32 allows you to specify the SDA (and SCL) pins of the I2C bus. Pass the USER_PIN constant to true for this The default I2C pins for major development boards are listed in this table.

#include <Arduino.h>
#include <Wire.h>

#define DISPLAY_ERROR false 
#define LOOP_DELAY    10000
#define USER_PIN      false

// Personnaliser les broches du bus I2C pour ESP8266 ou ESP32 
// Customize I2C bus pins for ESP8266 or ESP32
const int PIN_SCL = D1;
const int PIN_SDA = D2;

String I2Ctest() {
  byte error, address;
  int nDevices;
  String s;
 
  s="Scanning...\n";
 
  nDevices = 0;
  for(address = 1; address < 127; address++ ) {  
    Wire.beginTransmission(address);
    error = Wire.endTransmission();
 
    if (error == 0) {
      s+="I2C device found at 0x";
      if (address<16)
        s+="0";
        s+=String(address,HEX);
        s+="\n";
 
      nDevices++;
    } else if ( error > 0 ) {
      if ( DISPLAY_ERROR ) {
        s+="Unknow error at 0x";
        if (address<16)
          s+="0";
          s+=String(address,HEX);
          s+="\n";
      }  
    }    
  }
  if (nDevices == 0)
    s+="No I2C devices found\n";
  else
    s+="done\n";
  return s; 
}

void setup() {
  Serial.begin(115200);
  Serial.println("I2C scanner");
  #if USER_PIN
    Wire.begin(PIN_SDA, PIN_SCL);
  #else
    Wire.begin();
  #endif
}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.println(I2Ctest());
  delay(LOOP_DELAY);
}

Default pins of the I2C bus of the most common development boards

Here is the list of the default pins of the most common development boards.

It is possible to manually specify the I2C pins only for ESP32 and ESP8266.

	SDA	SCL	SDA1	SCL1
	Main bus		Secondary bus
Arduino Uno *	A4	A5
Arduino Ethernet	A4	A5
Arduino Mega2560	20	21
Arduino Leonardo	2	3
Arduino Due	20	21	SDA1	SCL1
ESP8266	D1	D2
ESP32 DevkitC v4	21	22	User	User
ESP32 (older generations)	IO21	IO22	User	User
STM32	PB7 or PB9	PB6 or PB8	PB11	PB10
Raspberry Pi (any generation)	3	5

(*) Do not use the pins marked SDA and SCL on the Arduino Uno.

Before you can use I2C components using the Raspberry Pi’s GPIO, you must first activate the bus. Follow the detailed instructions in this tutorial

I2C environmental sensors

Sensors for measuring temperature, humidity, atmospheric pressure, brightness.

Sensor	Measured	I2C address	Alternative address	Buy
BH1750	Light intensity 0 ~ 65535 lux 16 bit converter Technical documentation	0x23	0x5C If voltage on ADDR> 0.7 VDC	$6.50 as of 21 September 2021 3 h 11 min BUY NOW Amazon.com
Projects and articles on the BH1750FVI New LoLin W600-PICO and WeMos d1 mini compatible shields BH1750 (GY-302), measure the lighting quality of your home (Arduino / ESP8266 / ESP32)				$6.50 as of 21 September 2021 3 h 11 min BUY NOW Amazon.com
BMP180	Air pressure 300 ~ 1100hPa Technical documentation	0x77		$2.48 BUY NOW Ebay
BMP280	Temperature from -40 ~ +85 ° C Air pressure of 300 ~ 1100 hPa Technical documentation	0x76	0x77	$2.48 BUY NOW Ebay
BME280	Temperature from -40 ~ +85 ° C Humidity 0 ~ 100% Air pressure from 300 ~ 1100 hPa Technical documentation	0x76	0x77	$5.00 BUY NOW $19.99 2 new from $19.99 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com
BME680	Temperature of -40 ~ +85 ° C Humidity 0 ~ 100% Air pressure of 300 ~ 1100 hPa Technical documentation	0x76	0x77	$22.95 2 new from $22.95 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com $28.82 3 new from $23.99 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com
Projects and articles produced using a BMP180, BME280 or BME680 sensor How to store data on a micro SD card. Arduino code compatible ESP32, ESP8266 OLED display SSD1306 in MicroPython, example with a I2C digital barometer BME280 (or BMP180) IoT development based on Orange Pi, Arduino (Firmata), Nodejs, Blynk and Johnny-Five Start programming with Node Js and Johnny-Five: IoT and robotics based on Arduino, Raspberry Pi, Orange Pi ESP8266 (Web Client): Sending Data to Jeedom in TCP / IP Wireless (JSON API) – Part 1 Driving the GPIO of the ESP8266 (Web Server) from Domoticz to TCP/IP Wireless – Part 2 ESP Easy: firmware ESP8266 to create connected and home automation objects without programming ESP8266 (Web Client): Sending Data to Domoticz in TCP/IP Wireless (API/JSON) – Part 1 ESP8266 (Web Server – Part 5): how to use Google Charts to display gauges and charts ESP8266 (Web Server – Part 2): Interaction between Arduino code and HTML interface ESP8266 (Web Server – Part 1): Store the web interface in the SPIFFS area (HTML, CSS, JS) How to create a beautiful Web Interface for projects ESP8266 / ESP32 with Bootstrap ESP8266. Understand the Arduino code of a web server with HTML interface BMP180 (Arduino): how to create a numerical barometer sensor ESP Easy: How to add OLED SSD1306 display to an IoT ESP8266 project
DHT12	Temperature from -20°C ~ +60°C (±0,5°C) Humidity from 20 to 95% (±5°C)	0xB8		$2.65 BUY NOW
MLX90614	No contact temperature from -40 ~ +125°C	0x5A	0x01 to 0x7F	$11.88 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com
MS5611	Temperature from -40°C ~ +85°C Atmospheric Pressure from 10 ~ 1200 mbar	0x76
SHT30	Temperature de -40°C ~ +125°C Technical datasheet	0x44	0x45	Breakout $3.12 BUY NOW $11.90 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com More breakout, LoLin Shields
Projects and tutorials New LoLin W600-PICO and WeMos d1 mini compatible shields Test of the SHT30 shield for LoLin d1 mini, temperature and humidity in I2C (ESP8266)
SI7021	Température de -10 ~ 85°C Humidité de 0 ~ 80% Technical datasheet	0x40		$10.05 6 new from $6.95 as of 20 September 2021 3 h 09 min BUY NOW Amazon.com
TSL2561	Light Intensity from 188 μLux ~ 88000 lux Documentation technique	0x29	0x39 0x49	$8.25 6 new from $8.25 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com
TCS34725	RGB color sensor Technical datasheet	0x29

Current measurement

Sensor	Measured	I2C address	Alternative address	Buy
INA219	Direct current measurement up to 26V@3.2A Technical documentation	0x40	0x41 0x44 0x45	$6.29 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com $8.99 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com $17.39 2 new from $17.39 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com
Projects and articles

Detection of pollutants. C0, CO2

Sensor	Measured	I2C address	Alternative address	Buy
CCS811	eCO2, CO2 equivalent of 400ppm ~ 29206ppm eTVOC, Total Volatile Organic (or eCOV) equivalent up to 32768ppb Bus speed: 100kHz, 400kHz Technical documentation	0x5A	0x5B	$10.25 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com $10.66 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com $22.95 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com
Projects and articles

I2C thermal camera

Sensor	Measured	I2C address	Alternative address	Buy
AMG8833 / AMG8831	Thermal image 8×8 pixels (64 pixels) from -20°C to +80°C	0x69	0x68	$60.01 3 new from $60.01 as of 19 September 2021 3 h 02 min BUY NOW Amazon.com $76.86 as of 19 September 2021 3 h 02 min BUY NOW Amazon.com
Projects and articles Convert Arduino code into ESP Easy Mega plugin for ESP8266 / ESP32

Accelerometer, gyroscope, magnetometer

To remotely control a robotic arm, a drone, a game …

Comparative table of the most common breakouts, MPU6050, MPU9250 and ADXL345.

	MPU6050	ADXL345	MPU9250

Gyroscope (axes)	3	3	3
Gyroscope measurement game			± 250, ± 500, ± 1000, ± 2000 ° / sec
Accelerometer (axes)	3	3	3
Accelerometer measuring range	± 2g / ± 4g / ± 8g / ± 16g	± 2g / ± 4g / ± 8g / ± 16g	± 2g / ± 4g / ± 8g / ± 16g
Magnetometer (axes)			3
Magnetometer measuring capacity			± 4800µT
Total degrees of freedom (DOF)	6	6	9
I2C addresses	0x68 0x69	0x1C	0x68 0x0C
Max speed of the I2C bus	400 kHz	400 kHz	400 kHz
SPI	✓	✓	✓
Supply voltage	2.375V ~ 3.46V	2.0V ~ 3.6V	2.4V ~ 3.6V
Consumption		23 µA 0.1 µA (standby)	3.5mA
Operation	-40°C ~ 85°C	-40°C ~ 85°C	-40°C ~ 85°C
Technical documentation	Read	Read	Read

OLED and LCD screens on I2C bus

Equipment	Application	I2C address	Alternative address	Buy
LCD2004	4-line LCD display screen Technical documentation	0x27
SSD1306	Black and white OLED screens, 64×64 or 128×68 pixels	0x3C		128×64 pixels $6.99 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com $17.99 as of 21 September 2021 3 h 12 min BUY NOW Amazon.com More dimensions
Projects and articles Unpacking Wemos ESP32 LoLin clone with 0.96” SSD1306 monochrome OLED display OLED display SSD1306 in MicroPython, example with a I2C digital barometer BME280 (or BMP180) Portable WiFi Scanner with OLED Display (ESP8266): signal strength, connection test to a server Domoticz: Lua script to create a remote OLED display with ESP Easy Connect an I2C SSD1306 OLED display and an ESP-01 (ESP8266) Jeedom, create an OLED SSD1306 remote display with ESP Easy and HTTP request ESP Easy: How to add OLED SSD1306 display to an IoT ESP8266 project

Additional digital I / O expansion boards, RTC clock

Equipment	Application	I2C address	Alternative address	Buy
ADS1115	4 additional 16-bit A / D inputs Technical documentation	0x48	0x4B
DS1307	Real-time clock with optional battery backup	0x68
MCP23017	16 additional digital inputs / outputs, DIP28 box Bus speed: 100kHz, 400kHz, 1.7MHz Technical documentation	0x20	0x27	$1.74 BUY NOW FastTech $7.99 3 new from $4.99 as of 21 September 2021 3 h 13 min BUY NOW Amazon.com
PCF8574	8 additional digital inputs / outputs Bus speed: 100kHz, 400kHz, 1MHz Technical documentation	0x38	0x3F	$5.84 BUY NOW TOMTOP Technology Co., Ltd $5.99 ~~$6.99~~ as of 21 September 2021 3 h 13 min BUY NOW Amazon.com
PCA9685	16 12-bit PWM channels Technical documentation	0x40	0x7F