SERVO SYSTEM, APPARATUS COMPRISING A SERVO SYSTEM, SIGMA DELTA MODULATOR, AND INTEGRATED CIRCUIT COMPRISING A SIGMA DELTA MODULATOR

摘要

A servo system comprising an analog sigma delta modulator for generating a normalized digital error correction signal from first and second analog control signals. The sigma delta modulator comprises an analog low-pass filter, a quantizer delivering the digital error correction signal and a multiplying DA-converter in feedback arrangement between the output of the quantizer and the input of the low-pass filter for multiplying the feedback signals with the sum of the analog control signals.