Design and Distortion Analysis of a Power Delivery Network in the Presence of Internal Supply Noise

This article presents a novel relationship between the duty cycle and power supply noise (PSN) for a feedback control circuit of a dc-dc buck converter. The derived relation is equally valid for the other high-speed circuits. Based on the derived relation, the closed-form expressions of the harmonics quantities for the dc-dc buck converter (including feedback circuitry) and power delivery network (PDN) are developed. The derived expressions of the distortions include the effect of small variations at the power supply and input dc terminals. A combination of two techniques, the Volterra series and the estimation-by-inspection methods, are used to derive the nonlinear quantities. The estimation-by-inspection method is used to model the feedback circuit, including the effects of PSN. The Volterra series derive the nonlinear quantities of the converter. The analytical results are compared with the simulation results for both the examples (designed in 180-nm LDMOS technology) in terms of mean percentage error (MPE) and computational (CPU) time.