Patent ID: 7884655
Filing Date: 2011-02-08
Classification: H03L

Abstract:
1. Control circuitry, comprising: first control means operable to generate a first control signal, the first control signal being indicative of a relationship between an output signal and a first reference signal, and to generate said output signal in dependence upon said first control signal, the first control means being configured to tend to maintain a first desired relationship between the output signal and the first reference signal in response to said first control signal, wherein said first control means forms a first control loop configured to compensate for the effect of hiqh-frequency disturbances in said first desired relationship; and second control means configured to influence operation of said first control means in response to said first control signal by way of a second control signal so as to tend to maintain a second desired relationship between said first control signal and a second reference signal, wherein said second control means forms part of a second control loop configured to compensate for the effect of low-frequency disturbances in said first desired relationship by way of compensating for corresponding low-frequency disturbances in said second desired relationship.