The present invention provides a device for restoring a DC component in a differential digital data stream. The device comprises a first and second peak detector for detecting peaks in the differential digital data stream, a memory element for storing an average of the first and second detected peak signals during rich data patterns, an error signal selector for error signal selection, and a regulator for negative feedback of a selected error signal. The selected error signal is either the average of the detected peak signals stored on the memory element minus the signal at the output of the first peak detector, or the signal at the output of the second peak detector minus the average of the detected peak signals stored on the memory element