High quality analog CMOS and mixed signal LSI design

This paper presents an overview of high quality design methodology both in the analog CMOS and in the mixed signal LSI. The important design considerations in analog CMOS are first discussed. Not only taking the conventional methodology into account but also taking care of the process fluctuation, including V/sub T/ mismatch or 1/f noise, leading to robust and high quality analog CMOS circuits. For the rapid-growing high frequency applications, parasitic effects such as cross-coupled capacitance and substrate power loss are becoming serious issues. Thus it is demonstrated that pre- and post-layout simulations are vital to achieve target characteristics. The mixed signal LSI design today requires system-level simulation in order to meet the competitive performance specifications. The mixed-mode simulation, using SPICE, Verlog-D, and Verilog-A, which can concurrently handle analog and digital circuits, is shown to be essential to the overall mixed signal system design. The substrate noise or EMI need to be analyzed effectively under such an environment as well. Finally, accurate device parameter extraction, its careful reflection to above circuit designs, and fine parameter control in manufacturing for the active and passive devices are described.