锁相环实现取样式A／D转换的原理及电路

本文提出一种利用锁相环实现取样式Ａ／Ｄ转换的新方法，通过锁相环对输入信号进行频率变换，获得一等效延时△ｔ的采样信号；输入信号的等效采样次数及实际采样间隔根据其频率特性由微机编程控制。基于此原理设计出高频周期信号的数据采集系统。

The Principle and Circuit for Sampled A/D Transformation Realized by Phase-locked Loop

A new method of realizing sampled A/D transformation by phase-locked loop was presented. Applying pll frequency transformation to,the input signals, an equivalent sample delayed signal hi was obtained.According to the input signal frequecy property, the equivalent sampling numbers and actual sampling interval of the input signals were controlled by a microcomputer program. Based on this principle, a data sampling system of high frequency and periodic signals was designed.