Quartz Resonator & Oscillator Tutorial

2-14

Flicker PM noise in the sustaining circuit causes flicker FM

contribution to the oscillator output frequency given by:

where ff is the frequency offset from the carrier frequency f, QLis the

loaded Q of the resonator in the circuit, Lckt (1Hz) is the flicker PM

noise at ff = 1Hz, and t is any measurement time in the flicker floor

range. For QL = 106 and Lckt (1Hz) = -140dBc/Hz, sy(t) = 8.3 x 10-14.

( Lckt (1Hz) = -155dBc/Hz has been achieved.)

Oscillator Instabilities - Circuit Noise


	F. L. Walls & J. R. Vig, "Fundamental Limits on the Frequency Stabilities of Quartz Crystal Oscillators," IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 42, pp. 576-589, July 1995.

	E. S. Ferre-Pikal, F. L. Walls & C. W. Nelson, “Design Criteria for BJT Amplifiers with Low 1/f AM and PM Noise,” Proc. 1995 IEEE Int'l Frequency Control Symposium, pp. 305-313, 1995.