A low-distortion Sigma Delta capacitive microaccelerometer with self-test circuit

作者：Bai Xiaohui^*

来源：IEICE Electronics Express, 2015, 12(15): 20150554.

DOI：10.1587/elex.12.20150554

• low-distortion
• Sigma Delta capacitive microaccelerometer
• interface
• self-test circuit

A low-distortion Sigma Delta interface with self-test circuit is proposed for a closed-loop capacitive microaccelerometer. A fully feedforward architecture is used to reduce integrator output swing and decrease distortions of the Sigma Delta interface circuit, resulting in a reduction of power dissipation. A self-test circuit is proposed to measure the distortions of the microaccelerometer without using a vibration table. A fourth-order closed-loop capacitive microaccelerometer is proposed to verify the effectiveness of the technique. The interface circuit is designed and the chip is fabricated using a standard 0.35 mu m CMOS process. The capacitive microaccelerometer consumes 10mW from a 5V supply with a sampling frequency of 250 kHz. It achieves a noise floor of 9 mu g/Hz(1/2), and the self-test measurement results show that the resulting HD2 and HD3 of the microaccelerometerare -92.28 dB and -99.27 dB, respectively.

• 出版日期2015-8-10
• 单位黑龙江大学