CMOS Op-amp Circuit Synthesis with Geometric Programming Models for Layout-Dependent Effects

Yu Zhang,  Bo Liu,  Bo Yang,  Jing Li,  Shigetoshi Nakatake
The University of Kitakyushu


This paper addresses CMOS analog circuit synthesis in the nanometer process based on geometric programming models. In the current era of electronic integrated circuit (IC) manufacturing, the channel length modulation lambda as well as the layout-dependent effects (LDE) such as the shallow trench isolation (STI) stress and the well proximity effect (WPE) must be considered in the circuit synthesis because of the more and more shrinking process. In this paper, we provide the posynomial models of the analog circuit specification taking the lambda into account as well as introducing the curve fitting to the STI stress and the WPE based on the BSIM model. In the design case of a typical CMOS op-amp, with these LDE-aware models, we optimized the circuit by the geometric programming (GP) and showed that the optimal results satisfied the specification by the simulation.