Digital IC's (Integrated Circuits) are simply digital electronic circuits built or grown upon a substrate and then packaged nicely. Logic circuits are available in a great variety of configurations. Commonly called chips, the name refers to the chip-like piece of the larger wafer of semiconductor they are grown upon. They may be divided into families of similar technologies with similar electrical properties, but the functionaly identical logic circuits may be available in several of these. The key to understanding these will involve learning logic as well as becoming familiar with the practical electrical aspects. Often, several circuits are to be found on a single chip (here chip refers loosly to the IC package in whole.)
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