Title
Variability-Aware Design of Multilevel Logic Decoders for Nanoscale Crossbar Memories
Abstract
The fabrication of crossbar memories with sublithographic features is expected to be feasible within several emerging technologies; in all of them, the nanowire (NW) decoder is a critical part since it bridges the sublithographic wires to the outer circuitry that is defined on the lithography scale. In this paper, we evaluate the addressing scheme of the decoder circuit for NW crossbar arrays, based on the existing technological solutions for threshold voltage differentiation of NW devices. This is equivalent to using a multivalued logic addressing scheme. With this approach, it is possible to reduce the decoder size and keep it defect tolerant. We formally define two types of multivalued codes (i.e., hot and reflexive codes), and we estimate their yield under high variability conditions. Multivalued hot decoders yield better area saving than n-ary reflexive codes, and under severe conditions, reflexive codes enable a nonvanishing part of the code space to randomly recover. The choice of the optimal combination of decoder type and logic level saves area up to 24%. We also show that the precision of the addressing voltages when a high variability affects the threshold voltages is a crucial parameter for the decoder design and permits large savings in memory area. Moreover, a precise knowledge about the variability level improves the design of memory decoders by giving the right optimal code.
Year
DOI
Venue
2008
10.1109/TCAD.2008.2006076
IEEE Trans. on CAD of Integrated Circuits and Systems
Keywords
DocType
Volume
Multilevel Logic Decoders,decoder circuit,Multivalued hot decoder,Variability-Aware Design,decoder size,decoder type,Nanoscale Crossbar Memories,NW device,memory decoder,decoder design,reflexive code,better area saving,NW crossbar array
Journal
27
Issue
ISSN
Citations 
11
0278-0070
4
PageRank 
References 
Authors
0.60
12
7
Name
Order
Citations
PageRank
M. H. Ben Jamaa191.27
K. E. Moselund240.60
D. Atienza318224.26
D. Bouvet440.60
A. M. Ionescu540.60
Y. Leblebici613920.49
Giovanni De Micheli7102451018.13