An Automatic Synthesis Tool for Nanometer Low Dropout Regulator Using Simulation Based Model and Geometric Programming

This paper presents an efficient synthesis framework for Low Dropout Regulator (LDOs) automatic design to facilitate varieties of power management ICs applications. A four-stage synthesizer is proposed to deal with topology selection, transistor sizing, and layout generation automatically. The proposed approach correctly describes device behaviors in moderate and strong inversion regions for current optimization. Without trivial trial and error procedure, the "SPICE accuracy" device size mapping is provided, and the resulting layout is compact and regular while meeting analog design constraints. Using the proposed synthesis tool for LDO automatic design, a prototype chip has been successfully fabricated in 65nm CMOS process. The experimental results validate our methodology in industrial cases with high performance and meet all the target specifications.