Self-Adaptation Techniques for Mixed-Signal SiGe BiCMOS ICs

Self-adaptation and user-controlled adaptation are powerful techniques that can be used for stabilization and performance improvement of analog and mixed-signal ICs. Those techniques are particularly useful for silicon-germanium BiCMOS circuits that offer advanced operational characteristics desirable for ground-based and space-oriented electronics. This paper presents a set of self-adaptation techniques based on generating and combining currents that represent temperaturerelated and process-related parameter deviations of bipolar transistors and resistors in BiCMOS ICs. In combination with several well-known compensation methods, such as Beta compensation and duty-cycle stabilization, the proposed techniques lead to more stable characteristics of highperformance ICs with higher tolerance to variable external conditions. This is specifically important for space-related products that operate within harsh environments. The efficiency of the proposed self-adaptation design approach has been demonstrated through the development and successful testing of a high-speed delay line IC for clock and binary data signals. Application of the proposed approach is not limited to the presented example. It will be efficient for stabilization of any characteristic in silicon-germanium BiCMOS circuits that can be electrically manipulated.