Chapter 2 - Passive Components

Abstract

Electronic components are the building blocks of an electronic circuit, and all electronic circuits are created by joining components together. This was done by soldering wires between the terminals of components, but nowadays the connections are more likely to be made using metal tracks on an insulating board (a printed circuit board or PCB). Often both the connections and the components are all contained in a single piece of silicon, the integrated circuit (IC). In addition, components can be active or passive. Active components are used to copy (amplify) waveforms and to switch voltages and currents on and off under electrical control. Passive components always reduce the power of an input waveform, so that an output wave from a circuit, which contains only passive components is always at a lower power than (or the same power as) the input. Passive components do not need any additional steady voltage supply to enable them to deal with waveforms. A complete electronic circuit will normally consist of both active and passive components, arranged so that the passive components control the action of the active components and act as a path for signal waveforms. The most common passive components, resistors, capacitors, and inductors are discussed in this chapter. A diode is a passive component, but its construction follows the methods that are used for semiconductors (which are active components).