3—8译码器是由8个3输入“与非”门构成，采用VHDL语言描述，从行为、功能对3—8译码器进行描述，不仅逻辑设计的容易，而且阅读方便。-3-8 decoder input by 8 3 " and not"　the door structure, use of VHDL language descr iption, from the behavior and function of the 3-8 decoder is described, not only the logical design of the easy and convenient to read.