Newnes Digital Logic IC Pocket Book

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Modern CMOS Digital ICs

One of the most important events in the history of digital electronics was the development, in 1969, of the new IC technology known as CMOS. CMOS (Complementary-symmetry MOS-FET) digital IC elements have major advantages over TTL types. They are simple and inexpensive, consume near-zero quiescent current, have a very high input impedance, can operate over a wide range of supply voltages, have excellent noise immunity, and are very easy to use. In 1972, practical CMOS arrived on the commercial scene in the form of a brand-new medium-speed family of digital ICs known as the ‘4000’-series. This new family was not as fast as the TTL technology then in use in the rival ‘74’-series of digital ICs, but in the mid 1980s a new ...