Barkhausen criterion

Barkhausen criterion

[′bärk‚hau̇z·ən krī‚tir·ē·ən]
(electronics)
A criterion used to determine the stability of an oscillator circuit which states that, if the circuit is seen as a loop consisting of an amplifier with gain A and a linear circuit whose gain β(j ω) depends on frequency ω, then the loop will oscillate with a perfect sine wave at some frequency ω0 if at that frequency A β(j ω0) = 1 exactly, that is, if the magnitude of A β(j ω0) is exactly 1 and its phase is 0° or 360°.
References in periodicals archive ?
Though several 2-stage ring VCO can be composed by different delay stage, extra power is certainly needed to provide an excess phase shift for oscillation fulfilling well-known Barkhausen criterion.
This relation is commonly known as the Barkhausen criterion, which states that the loop gain must be 1 and the loop phase shill multiples of 360[degrees] to obtain oscillation.
Since the oscillator has a group delay, the Barkhausen criterion changes to
Since the second oscillator circuit is of the same type the first one, the Barkhausen criterion is also fulfilled for the two oscillator circuits in series, as the second oscillator is terminated with the correct impedance [Z.
The Barkhausen criterion for oscillation implies that the phaseshift in the loop must be zero and the gain equal to one.