Capacitive Type 3-Axis Accelerometer

Abstract

A capacitive type 3-axis accelerometer for general industrial use was developed by using micro machining technology. A stable structure over the temperature was found by FEM analyses and experiments. The mechanism of non-linearity and cross-axis interference caused by the structure and electronics circuit were explained. And compensation methods were shown. The capacitive type 3-axis accelerometer was assembled with its control circuit and evaluated the performance. Typical performance is as follows. Acceleration range is ±2g, operating temperature range is from -30°C to 75°C, sensitivity is 1V/g, cross-axis sensitivity is less than 1% and offset variation over the temperature is less than 2mg/°C.