Patent ID: 8901905

Claim:
A method of generating power from a switching device, the method comprising: generating an oscillating signal in the form of a series of pulse trains; randomly changing the switching frequency, or the on-time, or both the switching frequency and the on-time of the switching device; causing the switching device to change from a first frequency among a plurality of frequencies to a second frequency among the plurality of frequencies only at the end of a pulse train of the first frequency; and causing the second frequency to start at the beginning of its first pulse train such that no switching duty-cycle disturbance occurs at the time of the change from first to second frequency; and eliminating spurious noise by ensuring that a spur elimination condition governing the relationship between the plurality of frequencies is satisfied; wherein the spur elimination condition is satisfied when the ratio of the first frequency multiplied by the number of cycles of its pulse train to any other of the plurality of frequencies equals a rational number that is not an integer.