What is it?

This is ST Microelectronics' newest 9-axis motion sensor, the LSM9DS1, coupled with Measurement Specialties' high-accuracy MS5611 altimeter in a compact Teensy 3.1 add-on shield or as a stand alone breakout board for breadboard use. The board is hardwired for I2C and has a front solder jumper to enable the 4K7 pullups, if needed. There are also back solder jumpers to change the device address, to enable additional interrupts DENG and INTM at the edge pins, and to allow 3V3 power and GND to be supplied at the edge pins of the board. The design allows pins to be free on the Teensy 3.1 to support hardware SPI for other devices , if desired, or the user can choose to enable these other functions of the LSM9DS1 instead. Enabling power and ground to be taken from the edge pins transforms the sensor board into a traditional sensor breakout board for use in a breadboard circuit. The sensor is NOT 5 V tolerant though, so use a logic level converter if you want to drive it with a 5 V microcontroller.

Why did you make it?

I have designed sensor breakout boards for the LSM9DS0, which have proved popular on Tindie. I expect to keep making these available. The newest 9-axis motion sensing solution from ST is smaller (3 mm x 3.5 mm), has higher magnetometer resolution, and uses less power than the LSM9DS0. The LSM9DS0 offers a wider range of acceleration and has some features lacking in the LSM9DS1. Overall I would classify the LSM9DS1 as a modest improvement of ST's flagship 9-axis motion sensor. It remains to be seen whether there is any advantage in terms of accuracy or stability of the data output. This LSM9DS1+MS5611 sensor breakout offers the latest motion sensing and pressure sensor technology in a compact, versatile, and inexpensive package ready for your motion control applications.

What makes it special?

Like most of the appallingly small devices I offer here, this board packs a lot of capability in a small size. It represents the latest evolution in my design practice and includes all the tricks I have learned to get the most out of these feature-full sensors in a very small breakout board. The solder jumpers enable various modes of use of the sensors allowing their performance to be configured for your particular use case.

I have written a well-commented sketch that runs on the Teensy 3.1 (and with a few changes on the 3V3 Arduino Pro Mini) that parametrizes the registers, configures and initializes the sensors, calibrates the accel, gyro, and magnetometer, obtains the scaled data and performs sensor fusion using open-source Madgwick and Mahony sensor fusion filters.

Order the bare pc board from OSH Park and build your own board, or order one fully assembled and tested from me and see what this new sensor combination can do for you!