Lunch Bunches

2009 | 2008 | 2007 | 2006 | 2005

What are Lunch Bunches? Lunch Bunches have been held since the department was formed in the mid-1970s. They are informal gatherings (with lunch provided!), centered around a presentation by a faculty member, visitor, student, post-doc, or other CS community member.

Tuesday, November 17, 12:00 pm
Babak Hassibi, Professor of Electrical Engineering
105 Annenberg

Information Flow in Networks

Tuesday, December 1, 12:00 pm
Alain Martin, Professor of Computer Science
105 Annenberg

Knowledge is Power but Ignorance is Bliss: An introduction to Asynchronous Logic
We all know that the microprocessors in our computers use a clock. The clock enforces sequencing in a VLSI implementation of a digital computation. The clocking protocol relies on a knowledge of gate and wire delays that constitutes both an advantage and a drawback. Its advantage is simplicity. But as increasing parameter variability makes this knowledge less and less precise, the drawbacks are starting to outweigh the advantages.

In this talk, I will present an overview of asynchronous logic, a design approach for digital VLSI that does not use clock. I will show that delay insensitivity---i.e. the complete ignorance of delays---is impossible. Instead, I will introduce the concept of "quasi-delay-insensitivity'' (QDI), in which a minimal timing assumption, the "isochronic fork'' is sufficient for implementing any computation. I will briefly describe the several asynchronous microprocessors designed at Caltech, their robustness and efficiency in the presence of large parameter variations, and their energy efficiency. Finally I will argue that the use of asynchronous logic may be unavoidable for emerging technologies like nano (CNT and SNW) and organic electronic.

| top |