Thispaperdescribesthedesignofthefirst10-Gb/sCMOSclockanddatarecovery(CDR)circuit.Alinearphasedetector(PD)isintroducedthatcomparesthephaseoftheincomingdatawiththatofahalf-rateclock.TheCDRcircuitalsoincorporatesathree-stageinterpolatingringoscillatortoachieveawidetuningrange.