摘要
针对传统的电荷平衡型I/F转换电路存在对小信号测量实时性差的问题,在深入分析了小信号测量原理的基础上,提出了运用I/F+AD的方式来提高对微小加速度的实时测量能力。采用AD7367—5和EP2C70F672对I/F电路进行了补充,利用FPGA设计了计数测频模块和AD接口,并在软核NIOS II中加入自定义浮点指令增加了系统的执行速度,满足了计算的需要。测试表明,这是一种解决小加速度实时测量问题的有效方法。
In order to solve the poor real time performance of measuring small signal for traditional charge bal- ance I/F conversion circuit and improve the real-time measurement capability of tiny acceleration, a method via combining I/F and AD is proposed after deeply analyzing the principle of measuring tiny signal. AD7367--5 and EP2C70F672 are adopted to supplement for lfF circuit and FPGA is used to design modules of counting and fre- quency measurement and AD interface. Besides, custom floating-point instructions are added in soft core NIOSII to increase the execution real-time measurement speed of this system, which satisfies the need of computation. Test results show its validity of of tiny signals.
出处
《科学技术与工程》
北大核心
2012年第35期9486-9490,共5页
Science Technology and Engineering
