Harmonics related synchronization for switching regulators

Abstract

Disclosed is a system and method for synchronizing switching regulators in an electronic system so that switching interference from the regulators may be kept from a given spectral region of interest. The system does this by selecting a master clock frequency such that each of the switching frequencies corresponding to each of the switching regulators is a harmonic of a fundamental frequency. Further, the master clock frequency is selected so that none of the switching regulators, each of which are driven by an harmonic of the fundamental frequency, generates switching interference in the spectral region of interest. Each of the switching regulators has a synchronization clock, which multiplies or divides the master clock frequency by an allocated harmonic factor. Each harmonic factor is selected to that the switching frequency is within the operating range of the particular switching regulator.

1 . A method for synchronizing a plurality of switching regulators, comprising:
 selecting a master clock frequency;   selecting a plurality of harmonic factors corresponding to the plurality of switching regulators; and   applying a plurality of clock signals to the corresponding plurality of switching regulators, wherein each of the plurality of clock signals is based on the master clock frequency and the corresponding harmonic factor, and wherein the master clock frequency and the plurality of harmonic factors are selected so that substantially no switching interference occurs within a spectral region of interest.   
   
   
       2 . The method of  claim 1 , wherein applying the plurality of clock signals comprises multiplying the master clock frequency by the corresponding harmonic factor. 
   
   
       3 . The method of  claim 1 , wherein applying the plurality of clock signals comprises dividing the master clock frequency by the corresponding harmonic factor. 
   
   
       4 . The method of  claim 1 , further comprising detecting a switching interference spectra. 
   
   
       5 . The method of  claim 4 , wherein detecting the switching interference spectra comprises:
 collecting time domain data from the plurality of switching regulators; and   converting the time domain data into frequency domain data.   
   
   
       6 . The method of  claim 5 , wherein detecting the switching interference spectra further comprises:
 collecting an RF signal from an antenna; and   converting the RF signal into frequency domain antenna data.   
   
   
       7 . A computer readable medium encoded with software for synchronizing switching regulators, comprising:
 a program for selecting a master clock frequency;   a program for selecting a plurality of harmonic factors corresponding to the plurality of switching regulators; and   a program for applying a plurality of clock signals to the corresponding plurality of switching regulators, wherein each of the plurality of clock signals is based on the master clock frequency and the corresponding harmonic factor, and wherein the master clock frequency and the plurality of harmonic factors are selected so that substantially no switching interference occurs within a spectral region of interest.   
   
   
       8 . The computer readable medium of  claim 7 , wherein the program for applying the plurality of clock signals comprises a program for multiplying the master clock frequency by the corresponding harmonic factor. 
   
   
       9 . The computer readable medium of  claim 7 , wherein program for applying the plurality of clock signals comprises a program for dividing the master clock frequency by the corresponding harmonic factor. 
   
   
       10 . The computer readable medium of  claim 7 , further comprising a program for detecting a switching interference spectra. 
   
   
       11 . The computer readable medium of  claim 10 , wherein the program for detecting the switching interference spectra comprises:
 a program for collecting time domain data from the plurality of switching regulators; and   a program for converting the time domain data into frequency domain data.   
   
   
       12 . The computer readable medium of  claim 11 , wherein the program for detecting the switching interference spectra further comprises:
 a program for collecting an RF signal from an antenna; and   a program for converting the RF signal into frequency domain antenna data.