Research Perspectives on Dynamic Translinear and Log-Domain Circuits

The area of analog integrated circuits is facing some serious challenges due to the ongoing trends towards low supply voltages, low power consumption and high-frequency operation. The situation is becoming even more complicated by the fact that many transfer functions have to be tunable or controllable. A promising approach to facing these challenges is given by the class of dynamic translinear circuits, which are, as a consequence, receiving increasing interest. Several different names are used in literature: log-domain, exponential state-space, current-mode companding, instantaneous companding, tanh-domain, sinh-domain, polynomial state-space, square-root domain and translinear filters. In fact, all these groups are (overlapping) subclasses of the overall class of dynamic translinear circuits. This compilation of research findings comprises ten contributions, coming from dynamic-translinear researchers in Europe and North America. It has also been published as a special issue of Analog Integrated Circuits and Signal Processing, Volume 22, Numbers 2 & 3, March 2000.