The use of structured analogue electronics to optimise the design of analogue systems

Introduces the concepts of a structured analogue design technique. The technique is to design systems using a set of primary mathematical functions (these functions include addition, inversion, logarithm and anti-logarithm), which are implemented on an analogue array in silicon using some conventional and some new circuit ideas. The design of an analogue system then becomes one of developing a temperature independent equation, or set of equations, which describe the required behaviour and mapping this onto the silicon array. The complete set of analogue cells is shown in the paper along with their circuit implementation. As an example the paper will show an analogue multiplier implemented using the structured analogue technique and the design steps involved to produce a function whose response is temperature independent. The multiplier has been built using standard cells, the results show the accuracy of the technique, the advantage in terms of process independence and speed of design and the way the technique facilitates the use of CAD tools for the design of analogue circuits