可编程数字控制精密延时电路设计  

Design of programmable digital control precision timing circuit

作　　者：马凯[1,2] 王彦文[2] 

机构地区：[1]徐州医学院医学信息学院,江苏徐州221004 [2]中国矿业大学(北京)机电与信息工程学院,北京100083

出　　处：《中国测试》2014年第1期93-96,共4页China Measurement & Test

基　　金：国家自然科学基金仪器重点项目(50927805)

摘　　要：设计一种基于斜波式发生器原理可编程数字控制精密延时电路,用恒流源电路充放电和18位的DA转换器分别接入高速比较器的两端,DA转换器预先设定一电压基准,恒流源充电电容达到电压基准,高速比较器开始反转,形成一个触发脉冲信号,然后充电电容通过高速二极管快速放电重新计时。设计成18bit数字控制可编程动态范围2ps的采集时间间隔,提高采集信号的精度和频率。A high precision programmable precision time circuit implementation method based ramp type is introduced. A constant current source circuit of charge and discharge and 18 bit DA converter are respectively connected with both ends of the high speed comparator. A reference voltage is .set by the DA converter, and the constant current source charges the capacitor to a voltage reference, then the high-speed eomparator begins to turn and forms a trigger pulse signal. After that, the charging capacitor fast discharges through the high-speed diode to prepare for the next recloeking. The acquisition precision is improved by the design to 18 bit 2 ps small acquisition time interval and a higher frequency signal can be sampled.

关 键 词：信号采集 等效采样 延时电路 

分 类 号：TN977.1[电子电信—信号与信息处理] TP274.2[电子电信—信息与通信工程]