基于PCI总线的高精度大量程时间间隔计数器研制

提出了一种使用二级内插法的基于PCI总线的插卡式时间间隔计数器的设计方法,解决了精密时间间隔测量中精度和量程不能兼顾的问题。采用双通道交换测量法校准了START和STOP输入通道的时延,消除了这两个通道之间时延差异对测量结果的影响。该计数器结合CPLD技术和TDC技术,在保证测量精度的基础之上,扩展了测量范围,满足了实际应用需求。文章介绍了该计数器软硬件实现的方法,并通过与RS620比对测试检验了设计方案的正确性。测试结果显示,该计数器的测量范围为0~107 s,单次测量不确定度优于1 ns,多次测量标准差优于0.4 ns。

Design of high precision and large range time-interval counter based on PCI bus

Based on PCI bus principle,a new method of plug-in type time-interval counter was designed by using two-stage interpolation. The compatible problem of accuracy and range of time-interval measurement was solved.The Dual-channel Swap method was used to calibrate time delay of START and STOP channel. The effect caused by the difference between the two channels on the measurement results was eliminated. On the basis of ensuring the measurement accuracy,the measurement range was expanded by using the CPLD and the TDC technology,so the counter could meet the requirement of practical application. The software and hardware approach of the counter was described. The correctness of the design was verified by compared with the RS620. The test results show that the maximum measuring range of the counter is 107 s,the single measurement uncertainty better than 1ns and the standard deviation of repeat measurement is better than 0. 4 ns.