A single chip universal cable set-top box/modem transceiver

Interactive digital cable services like video-on-demand or cable modems require quadrature amplitude modulation (QAM) and demodulation for the physical layer interface. Television service functions include access control or authorization and set-top box interaction. The transceiver IC is a monolithic mixed signal device that encompasses the complete digital communications interface, compliant with the ITU-TJ.83 Annex A/B European and North American standards. Two on-chip PLLs, referenced to a single crystal, derive all necessary timing signals. The IC is implemented in 4-metal, 1-poly 0.35 /spl mu/m CMOS technology.