Research for Mixed Signal Electronic Technologies: A Joint Initiative Between NSF and SRC: Coupled Device and Circuit Simulation for Critical RF IC Blocks

Oregon State University, Corvallis OR

Investigators

Abstract

With the proliferation of RF ICs in consumer electronic products there is a critical need for simulation and modeling tools that enable first pass success in silicon. The trend towards integrating complete systems on a chip, requires very high performance digital, analog, and RF circuits to be integrated on the same silicon substrate. Successful integration of these complex systems requires new design tools and design approaches that significantly advance the state-of-the-art. Certain aspects of RF system performance are easier to characterize and verify in steady state. Examples of these are distortion, power, frequency, noise, and transfer characteristics such as gain and impedance. The proposed work focuses on developing a coupled device and circuit simulator that will accurately address the modeling and simulation needs of critical and noise sensitive analog and RF devices and circuits. A coupled device and circuit simulator provides a direct link between the IC fabrication technology, device design and the higher level of circuit design. Since the models from the device simulator (numerical models) are predictive, they can be used to evaluate the impact of technology on circuit performance. Additionally, this work provides the foundation for new design approaches that will advance the state-of-the-art for analog and RF circuits blocks. This research will focus on modeling, simulation, and design of high performance and high frequency analog and RF circuits. The key contributions of this work will be: A software architecture for incorporating general purpose device simulators in the coupled device and circuit simulator CODECS. The architecture will allow integration without extensive modifications to the device simulator and enable simulation of technologies such as SiGe and SOI, and also simulation of optical devices. This tool architecture also facilitates parallelization over a cluster of workstations. Availability of time-domain and frequency-domain steady-state simulation methods within one simulator. Numerical (physical) models and compact circuit models can be used within this simulator. Capability of simulating device-to-device interactions including substrate and thermal couplings. Coupled device and circuit noise simulation techniques for RF circuits. Validation of simulator with fabrication of improved designs for the following RF circuitry: low noise amplifier (LNA), mixer, and voltage controlled oscillator (VCO). These circuits are critical blocks in a transceiver and are particularly sensitive to noise. The research in this proposal is tightly integrated with a significant educational component. This will include development of courses in RF integrated circuits, and modeling and simulation for RF applications. A new undergraduate course will be developed. This course will focus on transceiver architectures and discrete design and will include a lab in which students will gain hands-on experience in radio design. The emphasis will be on projects related to transceiver design. The research results, including the software, circuit designs, and course-related materials will be available on the world wide web. In addition, results from the proposed work will be presented at meetings of the Semiconductor Research Corporation and the NSF Center for Design of Analog and Digital ICs.