A novel voltage controlled crystal oscillator circuit

A novel approach reported in this paper optimizes the dynamic noise and drive sensitivity factor for achieving low phase noise VCXO circuits. An example of mode-feedback and differential coupled crystal oscillators are demonstrated for the validation of this approach, which minimizes the phase noise for inexpensive low quality factor (Q) crystal resonator based oscillators. The noise reduction techniques described in this work offers cost-effective signal source solutions for consumer electronics applications where use of expensive high Q crystal resonator is unaffordable.