Noise suppression in switching power supplies

A method and apparatus for suppressing noise caused by the switching of a switching power supply. The method and apparatus use frequency dithering techniques to distribute the switching noise and its spurious products over a wider bandwidth, thereby reducing the average peak power per given range of bandwidth. The frequency dithering techniques are particularly applicable to mobile radio applications, where switching noise from switching power supplies can modulate the transmit carrier and its harmonics, sub-harmonics and intermediate frequency products.