A 2.7 V mixed signal processor for CDMA/AMPS cellular phones

This paper describes the design approach and test results of a monolithic mixed signal processor for use in dual-mode CDMA/AMPS (IS-95A) cellular phones. The processor interfaces between RF and digital baseband blocks. It comprises of a low jitter 9.8 MHz PLL, a high speed 4/8-bit CDMA/AMPS codec, channel filters, a 12-bit FM demodulator, a low power 13-bit voice codec and speech filters. The processor design is targeted for low power applications and fabricated in a low power 0.5 /spl mu/m CMOS technology. The statistical test results measured from -30/spl deg/C to +85/spl deg/C with a standard process variation demonstrate that the system completely fulfils IS-98A CDMA handset performance specification.