Analysis of the oscillation frequency and waveform amplitude for a high-frequency differential ring oscillator

In this paper, the oscillation frequency and waveform amplitude of a high frequency differential ring oscillator are analyzed and derived with a new platform. The obtained equations describe the nonlinear dependence of amplitude and frequency on the tail current, number of delay cell stages, and transistor sizes. The accuracies of the obtained equations are verified by the Cadence Spectre simulation results and experimental data. Compared with currently available expressions, the obtained equations show significantly improved accuracies; therefore they can be used to guide and facilitate high frequency differential oscillator design in submicron CMOS technology. The derivation platform can also be used to analyze other ring oscillator topologies.