New Crosstalk Avoidance Codes Based on a Novel Pattern Classification

TL;DR

This paper introduces a new classification of transition patterns for on-chip bus signals, leading to a novel family of crosstalk avoidance codes that better control delays and improve system performance across various technologies.

Contribution

It proposes a more detailed pattern classification and a new family of CACs that include existing codes and offer improved delay reduction and throughput.

Findings

More accurate delay control due to non-overlapping classes

New codes with reduced delays and higher throughput

Flexible approach adaptable to different technologies

Abstract

The crosstalk delay associated with global on-chip interconnects becomes more severe in deep submicron technology, and hence can greatly affect the overall system performance. Based on a delay model proposed by Sotiriadis et al., transition patterns over a bus can be classified according to their delays. Using this classification, crosstalk avoidance codes (CACs) have been proposed to alleviate the crosstalk delays by restricting the transition patterns on a bus. In this paper, we first propose a new classification of transition patterns, and then devise a new family of CACs based on this classification. In comparison to the previous classification, our classification has more classes and the delays of its classes do not overlap, both leading to more accurate control of delays. Our new family of CACs includes some previously proposed codes as well as new codes with reduced delays and improved throughput. Thus, this new family of crosstalk avoidance codes provides a wider variety of tradeoffs between bus delay and efficiency. Finally, since our analytical approach to the classification and CACs treats the technology-dependent parameters as variables, our approach can be easily adapted to a wide variety of technology.