BiCMOS, technology and circuit design

In this paper, the state-of-the art of combined bipolar/CMOS (BiCMOS) technologies and circuit techniques is described. Examples of advanced BiCMOS technologies for various applications will be given, together with theoretical considerations which allow a comparison of the bipolar and MOS transistors. New BiCMOS circuit techniques are presented for analog and digital applications. It will be shown that the BiCMOS technology offers some significant advantages for analog circuits, such as operational amplifiers, low impedance output stagers, and analog multipliers. Digital systems benefit from novel circuit technologies employed in buffers, interface circuits, logic gates, and large macrocells (e.g. multipliers, RAM, CAM). Several examples demonstrate the advantages of BiCMOS realizations over standard CMOS.