Ideal diode: The first approximation of a diode. The viewpoint is to visualize the diode as an intelligent switch that closes when forward-biased and opens…

Ideal approximation: The simplest equivalent circuit of a device. It includes only a few basic features of the device and ignores many others of less…

Hysteresis: The difference between the two trip points of a Schmitt trigger. When used elsewhere, hysteresis refers to the difference between the two trip points…

Hole: A vacancy in the valence orbit. For instance, each atom of a silicon crystal normally has eight electrons in the valence orbit. Heat energy…

Holding Current: The minimum current through a thyristor that can keep it latched in the conducting stage.

High-frequency border: The frequency above which a capacitor acts as an ac short. Also, the frequency where the reactance is one-tenth of the total series…

Heat Sink: A mass of metal attached to the case of a transistor to allow the heat to escape more easily.

Hartley oscillator: A circuit distinguished by its inductively tapped tank circuit.

Harmonics: A sine wave whose frequency is some integer multiple of a fundamental sine wave.

Hard Saturation: Operating a transistor at the upper end of the load line with a base current that is one-tenth of the collector current. The…

Half-wave rectifier: A rectifier with only one diode in series with the load resistor. The output is a half-wave rectified voltage.

h parameters: An early mathematical method for representing transistor action. Still used on data sheets.

Ground loop: If you use more than one ground point in a multistage amplifier, the resistance between the ground points will produce small unwanted feedback…

go/no-go test: A test or measurement where the readings are distinctly different, really high or really low.

Germanium: One of the first semiconductor materials to be used. Like silicon, it has four valence electrons.