摘要
探讨了V/F变换器组成的A/D转换电路中,采用定时器对周期信号采样精度出现偏差的问题,提出一种改进的V/F变换器组成的A/D转换电路,该电路采用前置信号调理电路,使得输入量的信号变化趋势与V/F变换器输出信号周期的变化趋势一致。在经过光耦器件耦合后,利用C8051Fxxx单片机可编程计数器阵列PCA,实现了多路A/D转换。实验表明,该方式采集精度高,速度快。在要求现场隔离的工况情况下,该电路有很好的应用场合。
The paper discusses the accuracy offset when using the timer to sample periodical signals in common A/D transform circuit composed of V/F converter, and proposes an improved circuit which adopts prepositve signal regulation to makes the change of input signals consistent with that of the period of output signals. The programmable counter array （PCA） of C8051 Fxxx is used to achieve multi - channel A/D transformation after the coupling of optical coupler. The experimental results show that this new method is faster and more accurate in signal collection, and it finds good applications when field isolation is required.
出处
《电子科技》
2008年第6期30-33,共4页
Electronic Science and Technology
