A 0.9 V 1.2 mA 200 MHz BiCMOS single-chip narrow-band FM receiver

Low-power single-cell battery-operated fully-featured radio receivers, with a minimum of external components are hard to find. Classical low-voltage heterodyne receivers consisting of bipolar transistor arrays require 50 to 60 external components to realize off-chip selectivity, filtering, demodulation, audio processing, etc. Zero or low intermediate frequency (IF) bipolar integrated circuit (IC) receivers with some on-chip base-band processing circuits require 25 to 40 components, but do not work at 0.9 V or drain more than 10 mA. This BiCMOS receiver IC is a full-featured single-conversion low IF narrow-band FM receiver that needs only 4 to 7 external components. This is made possible by a fully-integrated delay-line FM demodulator using parallelism that enables both automatic-frequency control (AFC) and muting to be realized at IF. Full functionality down to 0.9 V is obtained by ac coupling at radio frequencies (RF) and bulk forward biasing in the CMOS analog and digital building blocks. The receiver uses a BiCMOS process featuring vertical 3.6 /spl mu/m npn and pnp BJTs and 1.2 /spl mu/m 0.86 V V/sub Tmax/ MOS transistors. The chip area is 22 mm/sup 2/.