The effect of noise propagation on phase noise in ring oscillators

Abstract

The assumption that the white noise sources independently affect the phase noise and jitter in ring oscillators is revisited. Propagation of jitter originating from a noise source around the ring oscillator loop and its effect on phase noise are quantified. It is shown how, contrary to the commonly-held assumptions, the resulting jitter can in fact depend on the number of stages.

Wake-up Receiver Based Ultra-Low-Power WBAN

“…At RF frequencies the ring oscillator will never reach the full output voltage swing, but will always be a factor ε smaller, as was discussed in [56]. This effect is shown in figure 4.11, where A is the theoretical amplitude and εA is the actual amplitude.…”

“…This effect is shown in figure 4.11, where A is the theoretical amplitude and εA is the actual amplitude. The swing parameters used in [56] are given below. The parameters only depend on N; for a 4-stage ring oscillator, ε ≈ 0.839.…”

“…For the ring oscillator the phase noise model was presented in [59] and extended in [56], respectively. The quality factor Q for the LC oscillator is approximately equal to the quality factor of the tank inductor.…”

“…The quality factor Q for the LC oscillator is approximately equal to the quality factor of the tank inductor. The quality factor for the ring oscillator is used to fit Leeson's equation to the ring oscillator phase noise model given in [56]. The parameters for the ring and LC oscillators are given in table 4.2.…”

Requirement driven low-power LC and ring oscillator design

“…The two P type transistors in the load are biased in triode region. In RF frequency ring oscillators the full output swing will never be reached, but will always be a factor smaller, as was discussed in [4]. This effect is shown in figure 3, where A is the theoretical amplitude and A is the actual amplitude.…”