Introduction

While asynchronous circuits have undergone a renaissance driven by significant renewed interest in the last decade, their promises -- reduced power, increased performance, and robustness -- have only begun to be fully realized [34][3][17][12][25][11][14][27][15]. Although several of these methods have been effective, several synthesis steps still lack optimal solutions or practical tools. Likewise, a lack of well-integrated and extensible environments within which to embed these tools leaves designers without a smooth synthesis path. By contrast, the synchronous community possesses a wealth of such tools and environments, both commercial and academic [7], which benefit both researchers and end-users.

Thus, MINIMALIST makes contributions on several fronts:

• An integrated synthesis path consisting of state-of-the-art asynchronous synthesis algorithms:
  • CHASM, the first general optimal state encoding tool for asynchronous machines, providing both exact and fixed-length modes, and which can produce exactly-minimum output logic, a key parameter in asynchronous system performance
  • HFMIN, the only exact hazard-free symbolic two-level logic minimizer, supporting both single- and multi-output implementations
  • IMPYMIN, a new implicit exact hazard-free two-level logic minimizer, capable of solving all available benchmark problems in under 15 minutes, including several previously unsolvable problems
  • ESPRESSO-HF, a very fast new heuristic hazard-free two-level logic minimizer, which typically produces optimal or near-optimal results in under 3 seconds
  • Synthesis for testability, yielding -testable multi-level implementations under either stuck-at or robust path delay fault models, with little or no area overhead
• In contrast to existing synthesis paths, MINIMALIST provides a single synthesis path able to produce implementations in a variety of styles (e.g., single-output vs. multi-output, using vs. not using fed-back outputs as state variables, exploring various state code lengths) under various cost functions, allowing the exploration of design trade-offs
• The first complete and practical technology-independent synthesis path for burst-mode circuits using fast optimal algorithms
• An easily-usable environment with a software framework which can readily incorporate new tools

MINIMALIST currently supports widely-used plain burst-mode [18][28] specifications. Extended burst-mode specifications [38] will be supported in a forthcoming release.