INSTANT-ACQUISITION CLOCK AND DATA RECOVERY SYSTEMS AND METHODS FOR SERIAL COMMUNICATIONS LINKS

摘要

Methods and systems for recovering clock and data in data streams communicated over serial communications links. An exemplary serial communications receiver system includes a line receiver configured to receive a data stream from a serial communications link and an instant-acquisition clock and data recovery circuit coupled to the line receiver. The instant-acquisition clock and data recovery circuit includes a time interval detector and a sampling clock selector. The time interval detector is operable to sample the data stream received by the line receiver according to a multi-phase set of sampling clocks. The sampling clock selector is operable to designate one of the sampling clocks of the multi-phase set of sampling clocks as a recovered clock, based on a data transition in the received data stream detected by the time interval detector. The clock selector is configured to designate the sampling clock as the recovered clock independent of data transitions in the data stream that may have occurred prior to the data transition detected by the time interval detector.