Designing NULL Convention Combinational Circuits to Fully Utilize Gate-Level Pipelining for Maximum throughput
Abstract
Since the NULL Convention Logic (NCL) paradigm is delay-insensitive, NCL combinational circuits cannot be partitioned indiscriminately when pipelining, as can clocked circuits. Instead, these circuits must be partitioned into stages, such that each stage is input-complete with respect to all of its inputs and delay-insensitivity is maintained. Therefore the selected architecture for an NCL circuit may vary depending on whether or not the given circuit is to be pipelined. for example, the combinational circuit that has the shortest critical path may not necessarily result in optimal throughput when pipelined. This paper presents a method called Threshold Combinational Reduction for Pipelining (TCRP), to design NCL combinational circuits that will maximize throughput when pipelined. This method is demonstrated on the design of a 4-bit x 4-bit quad-rail multiplier and a dual-rail Booth2 multiplier, showing that both designs have an additional increased throughput after pipelining, when their combinational circuitry is designed using TCRP rather than the previous Threshold Combinational Reduction (TCR) method [1].
Recommended Citation
S. C. Smith, "Designing NULL Convention Combinational Circuits to Fully Utilize Gate-Level Pipelining for Maximum throughput," Proceedings of the International Conference on Embedded Systems and Applications ESA'04 - Proceedings of the International Conference on VLSI, VLSI'04, pp. 407 - 412, Institute of Electrical and Electronics Engineers, Dec 2004.
Department(s)
Electrical and Computer Engineering
Keywords and Phrases
Asynchronous logic design; Delay-insensitive circuits; NULL Convention Logic (NCL); Speedup; Threshold Combinational Reduction (TCR)
International Standard Book Number (ISBN)
978-193241541-4
Document Type
Article - Conference proceedings
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Institute of Electrical and Electronics Engineers, All rights reserved.
Publication Date
01 Dec 2004