Q Factor

Definition

Q factor is a measure of the quality of a resonant (tank) circuit.

A "high-Q" circuit has mostly reactive components (inductive and capacitive), with low resistance. It resonates strongly, with little damping (low loss). A high-Q circuit will have low bandwidth relative to its center frequency (that is, it will have a narrow bandwidth vs frequency curve).

Q = 2 π * (Energy stored / Energy dissipated per cycle)

Synonyms