A 2.488 Gb/s Si-bipolar clock and data recovery IC with robust loss of signal detection

SONET 2.488Gb/s transmission and switching systems, network backbones, and video transmission are among the many application areas benefiting from inexpensive and robust clock and data recovery circuits (CDR). Previous commercial solutions have required multiple chips and GaAs processes to perform this function. This 25GHz f/sub T/ Si-bipolar chip operates from 2 to 3Gb/s over worst-case process, temperature and voltage variations, dissipating 1.77W from 5V/spl plusmn/10% supply, requiring a single off-chip filter capacitor. For network monitoring, a loss-of-signal (LOS) detector operates on phase-error events, with a trigger threshold programmable between 10/sup -4/ and 10/sup -6/ BER.