Storage optimization by replacing some flip-flops with latches

Tsung-Yi Wu, Youn Long Lin

Research output: Chapter in Book/Report/Conference proceedingConference contribution

13 Citations (Scopus)

Abstract

Conventionally, when a synchronous sequential circuit is synthesized, storage units are implemented in either edge-triggered flip-flops or level-sensitive latches, but not both, depending on the clocking scheme (one- or two-phase) used. We propose that, in the former case, some of the flip-flops can be replaced with latches. Since a latch is generally smaller, faster and less power-consuming than a flip-flop, this replacement leads to improvements in circuit area, performance and power consumption. Whether a flip-flop can be replaced with a latch depends on not only its structural context but also its temporal behavior. In this paper, we first present conditions under which a straightforward replacement can be made; then, we propose two retiming-based transformations that increase the number of replaceable flip-flops. We have implemented the proposed idea in a software called FF2Latch. Experimental results on a set of control-dominated circuits from the high-level synthesis benchmark set [1] show that a large number of the flip-flops can be replaced with latches. Up to 22% reduction in the circuit area and up to 73% reduction in the power consumption have been achieved.

Original languageEnglish
Title of host publicationEuropean Design Automation Conference - Proceedings
PublisherIEEE
Pages296-301
Number of pages6
Publication statusPublished - 1996 Jan 1
EventProceedings of the 1996 European Design Automation Conference with EURO-VHDL'96 and Exhibition - Geneva, Switz
Duration: 1996 Sep 161996 Sep 20

Other

OtherProceedings of the 1996 European Design Automation Conference with EURO-VHDL'96 and Exhibition
CityGeneva, Switz
Period96-09-1696-09-20

Fingerprint

Flip flop circuits
Networks (circuits)
Electric power utilization
Sequential circuits

All Science Journal Classification (ASJC) codes

  • Control and Systems Engineering

Cite this

Wu, T-Y., & Lin, Y. L. (1996). Storage optimization by replacing some flip-flops with latches. In European Design Automation Conference - Proceedings (pp. 296-301). IEEE.
Wu, Tsung-Yi ; Lin, Youn Long. / Storage optimization by replacing some flip-flops with latches. European Design Automation Conference - Proceedings. IEEE, 1996. pp. 296-301
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Wu, T-Y & Lin, YL 1996, Storage optimization by replacing some flip-flops with latches. in European Design Automation Conference - Proceedings. IEEE, pp. 296-301, Proceedings of the 1996 European Design Automation Conference with EURO-VHDL'96 and Exhibition, Geneva, Switz, 96-09-16.

Storage optimization by replacing some flip-flops with latches. / Wu, Tsung-Yi; Lin, Youn Long.

European Design Automation Conference - Proceedings. IEEE, 1996. p. 296-301.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Wu T-Y, Lin YL. Storage optimization by replacing some flip-flops with latches. In European Design Automation Conference - Proceedings. IEEE. 1996. p. 296-301