Accurate determination of switching loss in class-D power amplifiers with random Gaussian excitation using Rice Formula

A well known technique to compute average zero crossing rate of statistical signals in Information Theory (Rice´s Formula) is employed to accurately predict the switching loss of the limit cycle class-D power amplifier. A closed-form formula is derived which is not only faster than circuit simulation but also very insightful for a priori design as it relates the switching loss to input signal statistics. The results obtained from the derived formulas have been verified by a prototype design of a CMOS voltage-mode class-D power amplifier. The correspondence between the results is satisfactory.