Sensirion I²C SFA3X Arduino Library

This is the Sensirion SFA3X library for Arduino allowing you to communicate with a SFA3X sensor over I²C.

Click here to learn more about the Sensirion SFA3X sensor.

The default I²C address of SFA3X is 0x5D.

Installation of the library

This library can be installed using the Arduino Library manager: Start the Arduino IDE and open the Library Manager via

Sketch ➔ Include Library ➔ Manage Libraries...

Search for the Sensirion I2C SFA3X library in the Filter your search... field and install it by clicking the install button.

If you cannot find it in the library manager, download the latest release as .zip file and add it to your Arduino IDE via

Sketch ➔ Include Library ➔ Add .ZIP Library...

Don't forget to install the dependencies listed below the same way via library manager or Add .ZIP Library

Dependencies

• Sensirion Core

Connect the sensor

Use the following pin description to connect your SFA3X to the standard I²C bus of your Arduino board:

Pin	Cable Color	Name	Description	Comments
1	red	VDD	Supply Voltage	3.15V to 5.5V
2	black	GND	Ground
3	green	SDA	I2C: Serial data input / output
4	yellow	SCL	I2C: Serial clock input
5	blue	SEL	Interface select	Pull to GND to select I2C (leaving it floating selects UART)

The recommended voltage is 3.3V.

Board specific wiring

You will find pinout schematics for recommended board models below:

Arduino Uno

SFA3X	SFA3X Pin	Cable Color	Board Pin
VDD	1	red	3.3V
GND	2	black	GND
SDA	3	green	D18/SDA
SCL	4	yellow	D19/SCL
SEL	5	blue	GND

Arduino Nano

SFA3X	SFA3X Pin	Cable Color	Board Pin
VDD	1	red	3.3V
GND	2	black	GND
SDA	3	green	A4
SCL	4	yellow	A5
SEL	5	blue	GND

Arduino Micro

SFA3X	SFA3X Pin	Cable Color	Board Pin
VDD	1	red	3.3V
GND	2	black	GND
SDA	3	green	D2/SDA
SCL	4	yellow	~D3/SCL
SEL	5	blue	GND

Arduino Mega 2560

SFA3X	SFA3X Pin	Cable Color	Board Pin
VDD	1	red	3.3V
GND	2	black	GND
SDA	3	green	D20/SDA
SCL	4	yellow	D21/SCL
SEL	5	blue	GND

ESP32 DevKitC

SFA3X	SFA3X Pin	Cable Color	Board Pin
VDD	1	red	3V3
GND	2	black	GND
SDA	3	green	GPIO 21
SCL	4	yellow	GPIO 22
SEL	5	blue	GND

Quick Start

1. Install the libraries and dependencies according to Installation of the library

2. Connect the SFA3X sensor to your Arduino as explained in Connect the sensor

3. Open the exampleUsage sample project within the Arduino IDE:

   File ➔ Examples ➔ Sensirion I2C SFA3X ➔ exampleUsage

4. Click the Upload button in the Arduino IDE or Sketch ➔ Upload

5. When the upload process has finished, open the Serial Monitor or Serial Plotter via the Tools menu to observe the measurement values. Note that the Baud Rate in the used tool has to be set to 115200 baud.

Contributing

Contributions are welcome!

This Sensirion library uses clang-format to standardize the formatting of all our .cpp and .h files. Make sure your contributions are formatted accordingly:

The -i flag will apply the format changes to the files listed.

clang-format -i src/*.cpp src/*.h

Note that differences from this formatting will result in a failed build until they are fixed. :

License

See LICENSE.