A 2.7-V CMOS single-chip baseband processor for CT2/CT2+ cordless telephones

A low-voltage, low-power CMOS single-chip baseband processor for CT2 and CT 2+ cordless telephones is presented, The chip integrates a complete voiceba nd codec, a tone generator, a G721 adaptive differential pulse code modulat ion coder/decoder, a burst-mode logic controller for CT2/CT2+ framings, and an I/Q baseband signal generator. The only external components are made of two quartz crystals. The chip is interfaced with standard microcontrollers through a parallel interface. With a 2.7-V minimum supply, it consumes normal and standby powers of 35 mW and 25 mu W, respectively. Maximum supply is 5.5 V, and temperature range is from -40 to 70 degrees C. Chip area (including scribe line) is 55.5 mm(2) in a 0.8-mu m N-well double -metal single-poly CMOS process with implanted capacitors.