摘要
本文首先论述了脉冲-电流转换原理,然后根据智能化仪器仪表的特点,采用一只十六位定时器和一位I-O口,设计了一套由数字量转化为模拟电流量的转换线路,并利用朗格拉奇插值方法对转换进行非线性补偿,使转化精度达到0.2级以上。测试结果表明这种转换方法比传统的采用D-A和V-I器件的转换方法具有成本低、精度高等优点,可以在各类带微处理器的仪器仪表中推广使用。
At first, the pluse/current transfer princplie is stated in this paper. Then, according to the character of intelligent instruments, a circuit used to transfer digital quantities to analogous current by using a sixteen bits timer and one bit output port is designed. The nonlinearing is compensated with the Lagrange insertion method. It is shown that this method has the character of lower cost and higher accuracy than the tradional transfer method with D/A and V/I part.It can be widely used in various types of instruments with microcomputer.
关键词
智能化仪表
电流输出方法
单片微机
intelligent instruments, a pluse/current transfer, a single chip micro-computer
