Letters to the editor

The article on Bipolar Gigabit Logic in Vol. 3, No. 1 by S. G. Knorr shows a circuit virtually identical to one first published by J. S. Brothers and myself in the 1968 ISSCC Conference. Plessey have built digital synthesizer chips based on such circuits for some ten years achieving toggle rates well into the gigabit range. It seems this work was so early that it has been forgotten and is now being reinvented. TOSHIBA gave an almost identical paper at last year´s IEDM.