An efficient linear-time variant simulation technique of oscillator phase sensitivity function

This paper presents a fast and accurate simulation technique to evaluate the impulse sensitivity function (ISF) of an oscillator. The proposed method, based on the linear-time variant (LTV) analysis of oscillators, computes the impulse phase response by means of periodic steady-state (PSS) and periodic transfer function (PXF) simulations available in commercial simulators (Spectre, Eldo, etc.). This technique overwhelms the classical simulation method based on transient analysis and injection of charge pulses along the oscillator period in terms of speed, precision and ease of use. The good accuracy of the proposed method has been verified in two oscillator topologies, namely a Van der Pol and a ring oscillator.