The design of high performance low cost BiCMOS op-amps in a predominantly CMOS technology

This paper provides a comparative study between a BiCMOS and CMOS version of a fully balanced, fully differential operational amplifier. Both amplifiers were fabricated through MOSIS, in a process optimized for MOS devices which also provides medium performance vertical isolated NPN transistors. By utilizing simple bipolar devices, the unity gain frequency was increased from 39.19 MHz to 52.05 MHz, and the slew rate from 39.5 V/μ-sec to 56.44 V/μ-sec while driving a 4 pF load by going to the BiCMOS version with the same power dissipation. The performance achieved would compare favorably with that obtained from a full-fledged BiCMOS process