2 – Schematic Drafting

Publisher Summary Schematic diagrams are used to represent graphically the components and interconnections of electrical circuits. Electronic schematics comprise symbols that represent the individual electronic parts used in the circuit. On a typical schematic, each symbol represents an individual part. The basic schematic symbols are highly standardized, since the most common parts like resistors and capacitors have been in use for almost a century. Some parts like logic ICs comprise subparts or gates. The part description must give concise information about all relevant electrical properties. An appropriate part description depends on the type of part. Micro and milli prefixes appear to be a problem if only upper case letters are used. Capacitors are classified according to the electrode and dielectric materials used in their construction. Other than surface mount devices, where a standard size code can easily be added to the part description, there are no real standards for capacitor sizes, and the manufacturer's part number should be included in the description.