SCHEMATIC FUNDAMENTALS:UNDERSTANDING THE SCHEMATIC CONNECTIVITY

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UNDERSTANDING THE SCHEMATIC CONNECTIVITY

In implementing the layout of any schematic, there is more to the final design than is explicitly shown. Connections appear on a schematic as a simple line drawn from point A to point B, or a simple connection of two transistors in series or in parallel. In reality, a line represents a signal path that needs to be physically implemented and optimized. Let’s look at an example (Figure 2.17).

The gates and transistors should look familiar, and the different transistor representations of the various gates have been described. The challenge now is to understand the connectivity of the devices. We have already seen that a bulk connection to each transistor is required but is not explicitly shown. Table 2.1 out- lines the different types of symbols.

Schematic Fundamentals-0010

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