EECS Colloquium: Challenges of Time-Interleaved ADCs

McDonnell Douglas Engineering Auditorium (MDEA)
Aaron Buchwald, Ph.D.

Senior Technical Director
InPhi Corporation

Abstract: The long-envisioned dream of moving the ADC of a communication receiver all the way to the antenna is fast becoming a reality. Recent ADCs that take advantage of time-interleaving and rely heavily on calibration enable new receiver architectures where the entire spectrum is digitized, leaving all channelization and demodulation functions to be accomplished in the digital domain. These "RF-to-Digital" systems have many advantages. However, the design of the requisite ADC remains a challenge to achieve wide-bandwidth and high-dynamic range while dissipating little power. This talk introduces key concepts of calibrated time-interleaved ADCs at a tutorial level. Examples of specific solutions are presented. Advanced concepts are also introduced. Finally, students wishing to pursue this area as a research topic will be exposed to several unsolved issues and hopefully will be inspired to extend the state-of-the-art with new and creative solutions.

Biography: Aaron Buchwald has 32 years experience in the field of analog-integrated circuit design. He is currently a senior technical director at InPhi Corporation. Before that he was a Fellow at Entropic Communications after its acquisition of Mobius Semiconductor, where he was CEO and founder. Prior to Mobius, Buchwald worked at Broadcom, where he helped build a world-class analog team emphasizing design in a mixed-signal environment. Buchwald's work on embedded CMOS Analog-to-Digital Converters (ADCs) enabled the production of single-chip cable set-top boxes and cable modems with integrated analog front ends and DSP circuitry. His work with Klaas Bult was awarded the best paper prize in 1997 at ISSCC. Later, Buchwald was responsible for development of high-speed serial transceivers (XAUI, CX4 and Fiber Channel) at Broadcom. The initial XAUI transceivers were some of the first to employ adaptive-receive equalization. Buchwald was formerly an assistant professor at the Hong Kong University of Science and Technology (HKUST). In his early career, Buchwald spent two years as an analog IC designer at Siemens in Munich, Germany. Prior to that, he spent four years at Hughes Aircraft Company in El Segundo, CA. Buchwald was born in Ames, Iowa, and received a BSEE from the University of Iowa, and an M.S. and Ph.D. from UCLA. He is co-author of the book "Integrated Fiber-Optic Receivers." He has taught professional short courses and tutorials on data converters and serial transceivers