Memsensing Accelerometers

Accelerometer measurement range selection depends on expected acceleration levels: 1) ±2g to ±4g for tilt sensing and static orientation

2) ±8g to ±16g for general motion sensing and handheld devices

3) ±50g to ±100g for vehicle dynamics and vibration monitoring

4) ±200g for crash detection and high-g shock applications. Choose a range that encompasses your maximum expected acceleration with 20-30% margin. Higher range sensors have lower sensitivity (mV/g or LSB/g), affecting resolution. For applications with both small and large accelerations, consider sensors with adjustable range settings.

Calculate your maximum expected acceleration and select a range with adequate margin. Contact our FAE for range selection guidance.

Noise density specifies the accelerometer's self-noise per square root of bandwidth, typically in ug/sqrt(Hz). Lower noise density enables detection of smaller accelerations. To calculate total noise: Noise = Noise Density × sqrt(Bandwidth). For example, with 200ug/sqrt(Hz) noise density and 100Hz bandwidth: Noise = 200 × sqrt(100) = 2000ug = 2mg. This determines the smallest acceleration you can reliably measure. High-resolution tilt sensing requires low noise density (<200ug/sqrt(Hz)), while crash detection can tolerate higher noise. Memsensing accelerometers offer competitive noise performance across all ranges.

Calculate required noise performance based on your smallest measurement signal and bandwidth. Select sensor with adequate noise margin.

Accelerometer bandwidth determines the maximum vibration frequency you can measure. Typical applications include: 1) Tilt sensing: 10-50Hz sufficient

2) Human motion: 50-100Hz captures most movements

3) Vehicle dynamics: 100-400Hz for suspension and handling

4) Vibration monitoring: 1-10kHz depending on machine type

5) Shock detection: >1kHz for fast transients. Higher bandwidth increases noise (noise proportional to sqrt(BW)). Most Memsensing accelerometers offer programmable bandwidth to optimize for your application. Select the minimum bandwidth that captures your signal of interest.

Identify the highest frequency of interest in your application and set bandwidth 2-3x higher. Use programmable bandwidth to optimize noise vs response.

Yes, MEMS accelerometers can measure static tilt by detecting the gravity vector component. When stationary, the accelerometer measures 1g along the vertical axis. As the sensor tilts, the gravity component shifts between axes, enabling tilt angle calculation. For best tilt accuracy: 1) Use low-g range (±2g) for maximum resolution

2) Select low-noise accelerometer

3) Implement temperature compensation

4) Use calibration to remove offset errors. Typical tilt accuracy of 0.1-1 degree is achievable with proper sensor selection and calibration. Memsensing low-g accelerometers are well-suited for tilt sensing applications.

For tilt sensing, select ±2g range with low noise density. Implement temperature compensation and calibration for best accuracy.

Automotive accelerometers (AEC-Q100 qualified) differ from consumer grade in several aspects: 1) Temperature range: automotive -40°C to +125°C vs consumer -20°C to +70°C

2) Reliability: automotive parts undergo rigorous qualification testing

3) Supply voltage tolerance: automotive handles wider voltage variations

4) EMC performance: automotive meets stricter EMC requirements

5) Traceability: automotive requires full production traceability

6) Price: automotive typically 2-3x consumer pricing. For vehicle applications, always use automotive-qualified sensors. Consumer sensors are suitable for non-safety vehicle accessories and general electronics.

Use automotive-qualified accelerometers for any vehicle safety or critical applications. Consumer grade is acceptable for non-critical accessories.