本文介绍了数据选择器的功能以及常见的几种数据选择器，重点介绍了四选一数据选择器74LS153 及其扩展 级联方式，详细分析了最常见的利用使能端进行扩展的级联方式，提出了一种不利用使能端且采用二级级联的方式扩展数据 选择器。

This paper introduces the function of data selector and several common data selectors, and introduces 4 to 1 data selector 74LS153 and its extended cascade way in detail, then analyzes the most common cascade way with enabling end. It proposes an extended data selector of two cascaded structure without the enabling and.