BMI325 | Bosch Sensortec | 6-axis IMU Inertial Measurement Unit (3-axis Accelerometer + 3-axis Gyroscope)

Specifications

- Package: LGA-14, 2.5×3.0×0.83mm, tape & reel delivery

- Supply Voltage: 1.71V ~ 3.63V, compatible with 1.8V/3.3V main controllers

- Accelerometer: ±2g / ±4g / ±8g / ±16g, software programmable; 16-bit

- Gyroscope: ±125 / ±250 / ±500 / ±1000 / ±2000 dps, software programmable; 16-bit

- Output Data Rate (ODR): 0.78125Hz ~ 6.4kHz

- Communication Interface: I2C + SPI + I3C, supports 2 hardware interrupt pins

- On-chip Buffer: 2KB FIFO

- Power Consumption

  - Standby Mode: 15μA

  - High-performance Mode: Typical 790μA

- On-chip Features: 16-bit on-chip temperature sensor, self-calibration, programmable low-pass filter, timestamp

- Operating Temperature: -40℃ ~ +85℃ (Consumer grade, non-AEC-Q100 non-automotive)

- Compliance: RoHS

Functions

Simultaneously measures 3-axis acceleration and 3-axis angular velocity (rotation). Integrated on-chip motion event engine. Hardware judges motion events and generates interrupt signals to reduce MCU workload:

1. Attitude detection, tilt measurement, angle calculation, device orientation recognition

2. Pedometer algorithm (step error approx. ±3%), motion / stationary detection, wake-up & sleep

3. Gesture recognition, pick-up detection, vibration detection

4. Free-fall detection, high-speed motion capture

5. Gyroscope with built-in temperature self-calibration to reduce thermal drift and improve attitude stability

> 

> Comparison with LIS2DW12: LIS2DW12 is only a 3-axis accelerometer; BMI325 is a 6-axis device (accelerometer + gyroscope) capable of attitude, angle and rotation detection.

## Applications

- Wearable devices: Smart watches, smart bands, TWS earbuds, smart rings (pedometer, lift-to-wake, attitude tracking, motion trajectory recording)

- Healthcare / sleep monitoring: Smart mattresses, patient monitoring beds for rollover, body movement and limb rotation detection. Compared with LIS2DW12, it can capture rotational movements.

- AR/VR controllers, remote controls, motion tracking equipment

- Battery-powered IoT devices: Asset tracking tags, wireless attitude sensors

- Consumer electronics: Phone & tablet screen rotation, smart glasses

- Portable instruments: Equipment vibration monitoring, tilt and attitude alarm

 Key Notes

1. 6-axis IMU integrated with gyroscope to measure rotation angle, ideal for projects requiring attitude and orientation calculation; LIS2DW12 is merely a 3-axis accelerometer and cannot measure rotation.

2. Supports high-speed I3C interface, widely adopted in new-generation wearable products.

3. Consumer grade, not suitable for direct automotive applications.
4. Pin-compatible with BMI323 for easy hardware upgrade.