Читать книгу Electronics All-in-One For Dummies - Lowe Doug, Doug Lowe - Страница 65

IN THIS CHAPTER

Examining how schematic diagrams provide a road map for electronic circuits

Looking at the most commonly used component symbols

Noting how voltage supply and common ground circuits are often drawn

Seeing how components are typically labeled

I love maps. I think I’ve kept every map I’ve used on every trip I’ve taken. I have big maps of entire countries and states, maps of cities, walking maps, maps of parks and museums, and even subway maps. My favorite maps are topographical maps of the areas where I’ve gone on weeklong backpacking trips. These maps show not only the routes I’ve hiked, but also elevation lines that represent every painful uphill step I’ve carried my 50-pound backpack up.

Without maps, we’d be lost. We’d never get to our destinations because we wouldn’t know where the roads are. Think of all the sights we’d miss along the way!

Electronics has its own form of maps. They’re called schematic diagrams. They show how all the different parts that make up an electronic circuit are connected.

Just as maps use symbols to represent features like cities, bridges, and railroads, schematic diagrams use special symbols to represent the different parts of a circuit, such as batteries, resistors, and diodes, and like maps, schematic diagrams have conventions that almost always are used. For example, positive voltages are almost always shown at the top of a schematic diagram, just as north is almost always shown at the top of a map.

In this chapter, you learn about the symbols used in schematic diagrams and the conventions used to draw them.