VLSI Circuit Techniques & Technologies for Ultra High Speed Data Conversion Interfaces

The performance of digital VLSI signal processing and communications systems is often limited by the data conversion interfaces between digital system-level components and the analog environment in which those components are embedded. The focus of this program has been research into the fundamental nature of such interfaces in systems that digitally process high-bandwidth signals for purposes such as radar imaging, high-resolution graphics, high- definition video, mobile and fiber-optic communications, and broadband instrumentation. Effort has been devoted to the study of both generic circuit functions, such as sampling and comparison, and architectural alternatives relevant to the implementation of high-speed data converters in present and emerging VLSI technologies. Specific results of the research include the design and realization of novel low-power CMOS and BiCMOS sampled-data comparators operating at rates as high as 200 MHz, the exploration of various design approaches to the implementation of high-speed sample-and-hold circuits in CMOS and BiCMOS technologies, and the design of a subranging CMOS analog-to-digital converter that provides 12-bit resolution at a conversion rate of 10 MHz.