Regular Analog/RF Integrated Circuits Design Using Optimization With Recourse Including Ellipsoidal Uncertainty

Abstract

Abstract-Long design cycles due to the inability to predict silicon realities are a well-known problem that plagues analog/RF integrated circuit product development. As this problem worsens for nanoscale IC technologies, the high cost of design and multiple manufacturing spins causes fewer products to have the volume required to support full-custom implementation. Design reuse and analog synthesis make analog/RF design more affordable; however, the increasing process variability and lack of modeling accuracy remain extremely challenging for nanoscale analog/RF design. We propose a regular analog/RF IC using metal-mask configurability design methodology Optimization with Recourse of Analog Circuits including Layout Extraction (ORACLE), which is a combination of reuse and shared-use by formulating the synthesis problem as an optimization with recourse problem. Using a two-stage geometric programming with recourse approach, ORACLE solves for both the globally optimal shared and application-specific variables. Furthermore, robust optimization is proposed to treat the design with variability problem, further enhancing the ORACLE methodology by providing yield bound for each configuration of regular designs. The statistical variations of the process parameters are captured by a confidence ellipsoid. We demonstrate ORACLE for regular Low Noise Amplifier designs using metal-mask configurability, where a range of applications share common underlying structure and application-specific customization is performed using the metal-mask layers. Two RF oscillator design examples are shown to achieve robust designs with guaranteed yield bound.

Robust Optimization for Gate Sizing Considering Non-Gaussian Local Variations

“…Design optimization affected by process introduced variations has been a focus of recent research efforts [11]- [14]. How to formulate the design optimization depends on the models of variations.…”

A two-step surrogate modeling strategy for single-objective and multi-objective optimization of radiofrequency circuits

“…In recent years, soft computing and, especially, evolutionary computation techniques, are attracting much attention for the design of analog and RF circuits (Alpaydin et al 2003;Fakhfakh et al 2005;Liu et al 2014a;Nieuwoudt et al 2007a;Nieuwoudt et al 2007b;Patanè et al 2016;Póvoa et al 2016;Ranter et al 2002;Tulunay and Balkir 2008;Vancorenland et al 2000;Xu et al 2009). The use of optimization-based design methodologies tries to overcome the limitations of traditional methodologies by using an algorithm that performs a wide exploration of the design space to find one optimal design (single-objective optimization) or several optimal designs by creating a Pareto optimal front (multi-objective optimization).…”

“…Several strategies for optimization-based RF circuit design have been proposed in the literature (Fakhfakh et al 2005;Liu et al 2014a;Nieuwoudt et al 2007a;Nieuwoudt et al 2007b;Patanè et al 2016;Póvoa et al 2016;Ranter et al 2002;Tulunay and Balkir 2008;Vancorenland et al 2000;Xu et al 2009). Reported approaches rely on accurate RF circuit simulators or faster, but inaccurate analytical equations to evaluate circuit performances within the optimization loop.…”

“…A lumped-element model (like the p-model in Fig. 1) relating inductors performance parameters (namely inductance and quality factor) with the inductor geometric parameters is used in other approaches (Nieuwoudt et al 2007a;Nieuwoudt et al 2007b;Vancorenland et al 2000;Xu et al 2009). However, these models are not accurate, especially at high frequencies (Passos et al 2015).…”