△-∑A/D转换器浅解

Simple analysis on △-∑A/D converter

运用形象解读的方法，对于△－∑Ａ／Ｄ转换器的基本原理进行了通俗释义。指出△－ ∑Ａ／Ｄ转换器的实质，在于如何用一个阶梯波形去充分拟合一个连续波形，并制取一张该阶梯波阶梯值的离散数据表。然后，按照实际采样率的要求，通过重采样的方法从其中抽取所需要的数据值，同时进行必要的去假频滤波。文章指出，为了制取这张虚拟的离散数据表，需要有△增量调制器和延时存储器的设置以及卷积运算的功能。为了进行去假频滤波和重采样以及二进制编码，需要有数字滤波器的设置。

The elementary principle of the △-∑ A/D converter is paraphrased in this paper.The essential of△-∑ A/D converter lies in how to use a staircase waveform to fully match an analog curve and then make a discrete data sheet of the staircase waveform. The required data is extracted from the data sheet by means of resampling according to the sampling rate. Meanwhile, the alias is filted. The paper points out that in order to make the dummy discrete data sheet, it is necessary to setup increment modulator and delay memory, along with the function of convolution.The digital filter is also needed to perform anti - alias filter, resampling and binary coding.