Patent ID: 8885376

Claim:
A switching regulator integrated circuit (IC), comprising: switching regulator circuitry arranged to produce an output which, when coupled to a storage inductor and storage capacitor, form a switching voltage regulator which produces an output voltage when in use, said output voltage including a ripple component having an associated fundamental frequency that varies with a frequency of a clock signal of the switching regulator circuitry; an inductor and a capacitor connected in parallel to form a resonant circuit having an associated notch filter frequency response that includes a resonant notch, said switching regulator circuitry and said resonant circuit housed within a common IC package; means for automatically trimming said clock signal frequency such that the resonant notch in said notch filter frequency response and said fundamental frequency are matched; and said switching voltage regulator and said resonant circuit arranged such that, when connected to receive said output voltage, said resonant circuit attenuates said ripple component; means for automatically trimming said clock signal frequency such that the resonant notch in said notch filter frequency response and said fundamental frequency are matched.