New feedback-stabilised analogue multiplier

An analogue multiplier consisting of controlled current-splitting devices and a feedback technique to stabilise its transfer characteristics is presented. An implementation of the technique making use of the exponential characteristics of the bipolar transistor is described. Results showing good agreement with theory are given. The features of the multiplier are: (i) Independence of transistor parameters (ii) Essential temperature independence (iii) Broadband application (iv) Designability (v) Potentially realisable in i.c. form