【摘要】 MEMS加速度计是一种基于硅微加工技术、用于测量加速度信息的惯性传感器，其接口电路的温度特性决定了整个传感器的性能。针对MEMS加速度计接口ASIC芯片全温条件下的零位输出漂移问题以及滞回特性问题，提出了三种温度特性优化方案。首先提出了阵列电容补偿方案，用于解决运算放大器失调、电容失配导致零位偏移所引起的温度特性问题；其次设计了低温漂带隙基准源，用于提供载波电平及共模电平；最后设计了三阶拟合数字温度补偿方案，进一步提高了输出精度。对该芯片进行测试，最终实测结果表明，在-45℃～85℃的温度范围内，MEMS加速度计三轴模拟输出漂移峰峰值分别为8 mg、12 mg、11 mg,补偿后可减小至2.8 mg以内，温度滞回误差均在2.5 mg以内；三轴数字输出漂移峰峰值分别为50 mg、22 mg、18 mg,补偿后可减小至6 mg以内，温度滞回误差均在0.5 mg以内。该研究为低温漂加速度计设计提供了技术支持和理论依据。更多还原

【Abstract】 The MEMS accelerometer is an inertial sensor based on silicon micromachining technology, which is used to measure acceleration information. The temperature characteristics of its interface circuit determine the performance of the entire sensor. In this paper, three temperature characteristic optimization schemes for the zero output drift and hysteresis characteristics of the MEMS accelerometer interface ASIC chip under full temperature conditions are proposed. Firstly, an array capacitor compensation scheme is proposed to solve the temperature characteristic problems caused by operational amplifier offset and capacitor mismatch leading to zero offset. Secondly, a low-temperature-drift bandgap reference source is designed to provide carrier level and common mode level. Finally, a third-order fitting digital temperature compensation scheme is designed to further improve the output accuracy. The chip is tested, and the final measured results show that within the temperature range of-45℃ to 85℃, the peak-to-peak drift of the three axes analog output for the MEMS accelerometer is 8 mg, 12 mg, and 11 mg respectively, which can be reduced to within 2.8 mg after compensation, and the temperature hysteresis error is within 2.5 mg. The peak-to-peak drift of the three axes digital output is 50 mg, 22 mg, and 18 mg respectively, which can be reduced to within 6 mg after compensation, and the temperature hysteresis error is within 0.5 mg. This paper provides technical support and theoretical basis for the design of low-temperature-drift accelerometers.更多还原