采用磁阻传感器与加速度计的电子罗盘设计

Design of Electronic Compass with Magnetoresistive Sensor and Accelerometer

基于磁阻传感器与加速度倾角计的电子罗盘由微控制器实现角度换算与输出。16位计数器对加速度计输出脉宽信号中断计数,磁阻传感器3轴输出的差分信号转换均由24位A／D直接转换,全部实现信号无缝直连。利用磁阻芯片的置位／复位电流带通的正反脉冲消除系统温度漂移及偏移,其软件以数字低通滤波器滤除随机干扰。

For the electronic compass based on magnetoresistive sensor and accelerometer, angle conversion and output is realized by microcomtroller. The 16-bit counters in the system are adopted to count the pulse-width of the signal that is outputted directly by the accelerometer through interrupt counting. The conversion of difference signal outputted by the three axles of magnetoresistive sensor is realized via 24-bit A/D. And the temperature drift and offset of the system is compensated with bi-directional current pulse through the set/reset strap in magnetoresistive sensor. On software, a digital low-pass filtering is used to cancel random interference