April 2010

Doc ID 17289 Rev 1

1/18

AN3182

Application note

Tilt measurement using a low-g 3-axis accelerometer

Introduction

This application note describes the methods and techniques for measuring tilt angles from a

low-g 3-axis accelerometer. The LIS331DLH 3-axis digital accelerometer is used as an

example in this document. Other 3-axis analog or digital accelerometers may also be

applied to the tilt angle measurement procedures described here, depending on their

respective specifications.

The ultra-low power LIS331DLH digital accelerometer is housed in a 3 x 3 x 1 mm LGA-16

external ADC chip is required. It also features a dynamically user-selectable full-scale

measurement range of ±2 g / ±4 g / ±8 g, with output data rates from 0.5 Hz to 1 kHz.

Section 1 of this application note introduces the terminology and parameters related to the

accelerometer, while Section 2 presents the accelerometer calibration techniques. Section 3

describes the tilt sensing theory and the methods of determining tilt angle measurement.

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