Noise in Frequency-Sensitive ESR Detectors

In this paper we present a method to compute analytical expressions for the phase and frequency noise in integrated CMOS LC tank oscillators. Our approach combines advanced MOS transistor modeling using the EKV model with the solution of stochastic differential equations modeling the behavior of the noisy oscillator. Using these results, we can calculate the noise floor in a new class of electron spin resonance (ESR) detectors presented in Yalcin and Boero (2008) and thereby provide estimates for the limit of detection for this type of frequency sensitive ESR detectors. The theoretical results are verified against simulations performed in a commercial simulation tool as well as measured data obtained from a CMOS prototype of the frequency sensitive ESR detector.