Shahriar Moinian

Computer-aided circuit analysis tools for RFIC simulation: algorithms, features, and limitations

The design of the radio frequency (RF) section in a communication integrated circuit (IC) is a challenging problem. Although several computer-aided analysis tools are available for RFIC design, they are not effectively used, because there is a lack of understanding about their features and limitations. These tools provide fast simulation of RFICs. However, no single tool delivers a complete solution for RFIC design. This paper describes the shortcomings of conventional SPICE-like simulators and the analyses required for RF applications with an emphasis on accurate and efficient simulation of distortion and noise. Various analysis methods, such as harmonic balance, shooting method, mixed frequency-time methods, and envelope methods, that are currently available for RFIC simulation are presented. Commercial simulators are compared in terms of their functionalities and limitations. The key algorithmic features and the simulator-specific terminology are described.

Integration of high-Q inductors in a latch-up resistant CMOS technology

Inductors fabricated using CMOS technologies based on epi/p/sup +/ substrates are severely degraded because of eddy current losses in the substrate. We propose and demonstrate a modified substrate structure, which addresses the conflicting goals of high inductor quality-factor and high latch-up immunity. Results include fabricated inductors with Q-factor as high as 16.

Overview of computer-aided analysis tools for RFIC simulation: Algorithms, features, and limitations

Design of the RF section in a communication IC is often a challenging problem. Although several computer-aided analysis tools are available they are not effectively used because there is a lack of understanding about their features and limitations. This paper attempts to explain the simulator-specific terminology without resorting to mathematical details. The shortcomings of conventional SPICE-like simulators and the analyses required for RF applications are described. Various analysis methods that are currently available for RF simulation are presented and commercial simulators are compared in terms of their functionalities and limitations.