Parametric yield optimization for MOS circuit blocks

Abstract

Two techniques are presented for optimizing the parametric yield of digital MOS circuit blocks for VLSI designs. The first is based on quasi-Newton methods and utilizes the gradient of the yield. A novel technique for computing this yield gradient is derived and algorithms for its implementation are discussed. Geometrical considerations motivate the second method which formulates the problem in terms of a minimax problem. Both yield optimization techniques utilize transient sensitivity information from circuit simulations. Encouraging results have been obtained thus far; several circuit examples are included to demonstrate these techniques.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>