Diff Amp: A two-transistor circuit whose ac output is an amplified version of the ac input signal between the two bases.

Diac: A silicon bilateral device used to gate other devices such as triacs.

Derived Formula: A formula or an equation that is a mathematical rearrangement of one or more existing equations.

Derating Factor: A value that tells you how much to reduce the power rating for each degree above the reference temperature given on the data…

Depletion-mode MOSFET: A FET with an insulated gate that relies on the action of a depletion layer to control the drain current.

Depletion Layer: The region at the junction of p- and n- type semiconductors. Because of diffusion, free electrons and holes recombine at the junction. This…

Defining Formula: A formula or an equation used to define or give the mathematical meaning of a new quantity. Before the defining formula is used…

Decibel Voltage Gain: This is a defined voltage gain given by 20 times the logarithm of the ordinary voltage gain.

Decade: A factor of 10. Often used with frequency ratios of 10, as in a decade of frequency referring to a 10 :1 change in…

DC Value: The same as the average value. For a time-varying signal, the dc value equals the average value of all the points on the…

DC-to-DC Converter: A circuit that converts dc voltage of one value to dc voltage at another value. Usually, the dc input voltage is chopped up…

DC Return: This refers to a path for direct current. Many transistor circuits won't work unless a dc path exists between all three terminals and…

DC Equivalent Circuit: What remains after you open all capacitors.

DC Beta (βdc): The ratio of the dc collector current to the dc base current.

DC Alpha (αdc): The dc collector current divided by the dc emitter current.