Analysis and modelling of buck converters output spectrum in CCM with PWM control

Simple and handy formulas for describing the spectrum of switching noise at the output of buck converters in CCM with resistive loads are derived. The formulas can be used by analog/RF designers to predict and account for power supply noise early in the design process. The results of those theoretical formulas are compared to the simulation results using verilog-A macro models, and further verified by measuring the noise spectrum of a standard on-the-shelf buck converter commonly used for large mixed-signal SoCs.