Pololu AltlMu-10 v4 Gyro, Accelerometer, Compass, and Altimeter (L3GD20H, LSM303D, and LPS25H Carrier)
The Pololu AltIMU-10 v4 is a compact (1.0″ × 0.5″) board that combines ST’s LPS25H digital barometer, L3GD20H 3-axis gyroscope, and LSM303D 3-axis accelerometer and 3-axis magnetometer to form an inertial measurement unit (IMU) and altimeter; we therefore recommend careful reading of the LPS25H datasheet (1MB pdf), L3GD20H datasheet (3MB pdf), and LSM303D datasheet (1MB pdf) before using this product. These sensors are great ICs, but their small packages make them difficult for the typical student or hobbyist to use. They also operate at voltages below 3.6 V, which can make interfacing difficult for microcontrollers operating at 5 V. The AltIMU-10 v4 addresses these issues by incorporating additional electronics, including a voltage regulator and a level-shifting circuit, while keeping the overall size as compact as possible. The board ships fully populated with its SMD components, including the L3GD20H, LSM303D, and LPS25H, as shown in the product picture.
The AltIMU-10 v4 features a newer pressure sensor than its predecessor, the AltIMU-10 v3, enabling pressure and altitude measurements with higher accuracy and lower noise, but the two boards are otherwise identical. Compared to the original AltIMU-10, the v4 version offers a number of improvements arising from the use of newer MEMS sensors, including a wider maximum magnetic sensing range and better gyroscopic accuracy and stability. This version also adds a pin for changing the sensor slave addresses, allowing two AltIMUs to be on the same I²C bus.
The AltIMU-10 v4 is pin-compatible with both the v3 version and the original AltIMU-10, but changes in I²C addresses and configuration registers might require some changes to software written for the older version (this should not be an issue if you are using our Arduino libraries). It is also pin-compatible with the MinIMU-9 v3 and offers the same functionality augmented by a digital barometer that can be used to obtain pressure and altitude measurements. It includes a second mounting hole and is only 0.2″ longer than the MinIMU-9 v3. Any code written for the MinIMU-9 v3 should also work with the AltIMU-10 v4.