The author introduces the process of using NE555circuit and a few fittings to make a tutamen of automatic refrigerator with functions of over-pressure, deficient pressure, and delay.

本文介绍了一种只用一块NE555时基电路和少量分立元件，就能制作一个具有过压、欠压和断电延迟三种保护功能的全自动电冰箱保护器。