The Adafruit BMP581 Precision Barometric Pressure and Altimeter Breakout delivers 0.4Pa relative accuracy (3.3cm altitude), I2C/SPI support, 0.5C temperature sensing, and STEMMA QT/Qwiic connectors, making it ideal for precise environmental and altitude measurement projects.

Bosch has been a leader in barometric pressure sensors, from the BMP085, BMP180, BMP280, BMP388,BMP390… now we’ve got the next generation, theAdafruit BMP58x Precision Barometric Pressure and Altimeter Breakout. As you would expect, this sensor is similar to its earlier versions buteven better. The BMP581 boasts improved precision, making it an excellent choice for environmental sensing or as a precision altimeter. It can even be used in either I2C or SPI configurations.

The BMP58x is the next-generation of sensors from Bosch and is the upgrade to the BMP2xx and BMP3xx – with a low-altitude noise as low as 1cm (0.08Pa) and the same fast conversion time. Similar to the previous BMP280, you can use either I2C or SPI. For simple, easy wiring, go with I2C. If you want to connect a bunch of sensors without worrying about I2C address collisions, go with SPI.

This sensor has an astonishingrelative accuracy of0.4 Pascalsat 900-1100 hPa and 25C, which translates to about 3.3 centimetres of altitude (compare to the BMP280’s 12 Pascal/1 meter and BMP388’s 8 Pascal/0.5 meter). The typical absolute accuracy is 30Pa or about 2.5 meters. Check the datasheet for how temperature and altitude can affect the absolute/relative accuracy.

The BMP581 is software/firmware compatible with the BMP580, but has more accurate/precise measurements.It’s also more expensive! So pick this when accuracyis more important than cost.

The datasheet sort of implies they intend this sensor to be used for drones and quadcopters, to keep altitude stable, but you could also use this for wearables or any project that wants to track height-above-sea-level. Note that for absolute height, you’ll still need to enter the barometric pressure at sea level if the weather changes, but that’s true of every altimeter sensor that uses pressure. You can also measure temperature with 0.5C accuracy.

Nice sensor, right? So we made it easy for you to get right into your next project. The surface-mount sensor is soldered onto a custom-made PCB with a 3.3V regulator and level shifting so you can use it with a 3V or 5V logic microcontroller without worry. It’s in the STEMMA QTform factor, making it easy to interface with. TheSTEMMA QT connectorson either side are compatible with theSparkFun QwiicI2C connectors. This allows you to make solderless connections between your development board and the BMP58xor to chain it with a wide range of other sensors and accessories using acompatible cable. Please note, the QT Cable is not included, but we have a variety in our Qwiic andSTEMMA QTsection.

Check out the Arduino library to get data out in under 10 minutes!

Resources

• Primary Guide: Adafruit BMP580, BMP581, and BMP585 – Temperature and Pressure Sensor

Package Contents

• 1x Adafruit BMP581 I2C or SPI Temperature and Pressure Sensor – STEMMA QT
• 1x 8-pin header