|
For Full-Text PDF, please login, if you are a member of IEICE,
or go to Pay Per View on menu list, if you are a nonmember of IEICE.
|
On-Chip Cache Architecture Exploiting Hybrid Memory Structures for Near-Threshold Computing
Hongjie XU Jun SHIOMI Tohru ISHIHARA Hidetoshi ONODERA
Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Vol.E102-A
No.12
pp.1741-1750 Publication Date: 2019/12/01 Online ISSN: 1745-1337
DOI: 10.1587/transfun.E102.A.1741 Type of Manuscript: Special Section PAPER (Special Section on VLSI Design and CAD Algorithms) Category: Keyword: standard-cell memory, SRAM, near-threshold computing, cache memory, system-on-chip,
Full Text: PDF(1.7MB)>>
Summary:
This paper focuses on power-area trade-off axis to memory systems. Compared with the power-performance-area trade-off application on the traditional high performance cache, this paper focuses on the edge processing environment which is becoming more and more important in the Internet of Things (IoT) era. A new power-oriented trade-off is proposed for on-chip cache architecture. As a case study, this paper exploits a good energy efficiency of Standard-Cell Memory (SCM) operating in a near-threshold voltage region and a good area efficiency of Static Random Access Memory (SRAM). A hybrid 2-level on-chip cache structure is first introduced as a replacement of 6T-SRAM cache as L0 cache to save the energy consumption. This paper proposes a method for finding the best capacity combination for SCM and SRAM, which minimizes the energy consumption of the hybrid cache under a specific cache area constraint. The simulation result using a 65-nm process technology shows that up to 80% energy consumption is reduced without increasing the die area by replacing the conventional SRAM instruction cache with the hybrid 2-level cache. The result shows that energy consumption can be reduced if the area constraint for the proposed hybrid cache system is less than the area which is equivalent to a 8kB SRAM. If the target operating frequency is less than 100MHz, energy reduction can be achieved, which implies that the proposed cache system is suitable for low-power systems where a moderate processing speed is required.
|
open access publishing via
|
|
|
|
|
|
|
|