1/f noise synthesis model in discrete-time for circuit simulation

Flicker noise, popularly known as 1/f noise is a commonly observed phenomenon in semiconductor devices. To incorporate 1/f noise in circuit simulations, models are required to synthesize such noise in discrete time. This paper proposes a model based on the fact that 1/f processes belong to the class of statistically self-similar random processes. The model generates 1/f noise in the time domain (TD) with a simple white noise input and is parameterized by a quantity whose value can be adjusted to reflect the desired 1/f parameter, that is, the slope of the 1/f spectrum. It thus differs from most of the earlier modeling approaches, which were confined to the spectral domain. To verify fit between the model and actual 1/f noise measurements, experiments were conducted using discrete devices such as a PIN photodiode at various bias conditions and sampling frequencies. The noise synthesized by the model was found to provide a good match to the measurements. Furthermore, it is demonstrated that the proposed 1/f noise model can also be incorporated in circuit simulations as a noise current or noise voltage source, which was not feasible earlier with the conventional spectral domain representation. To validate the inclusion of 1/f noise in circuits as TD current or voltage, simulations were carried out on a CMOS ring oscillator and the clock jitter due to 1/f noise was investigated.