说明：  推荐一份:"高速 CMOS 数字集成电路 实用单元电路辑",在单片机大量使用的今天,似乎被忘记的许多优质价廉的好电路....,温故知新,值得参考.
(Recommended a: " high-speed CMOS digital integrated circuits and practical cell circuit series" , today widely used in single-chip, it seems to be forgotten a good many high-quality low-cost circuit ...., learn new things, worth considering.)