Multi Vt 7T Sram cell for high speed application at 45 Nm technology

The trend of decreasing device size and increasing chip densities involving several hundred millions of transistors per chip has resulted in tremendous increase in design complexity. Low power SRAMs are essential in today's demand as they are preferred as on chip memories with read write stability. This paper presents a method based on multi-Vt to increase read, write stability and reduce the total leakage power dissipation of SRAMs while maintaining their performance. The proposed method is based on the observation that read and write delays of a memory cell in an SRAM block depend on the physical distance of the cell from the sense amplifier and it is also depend on Vt.

[1]  R. Heald,et al.  Variability in sub-100nm SRAM designs , 2004, ICCAD 2004.

[2]  Massoud Pedram,et al.  Reducing the Sub-threshold and Gate-tunneling Leakage of SRAM Cells using Dual-Vt and Dual-Tox Assignment , 2006, Proceedings of the Design Automation & Test in Europe Conference.

[3]  Ping Wang,et al.  Variability in sub-100nm SRAM designs , 2004, IEEE/ACM International Conference on Computer Aided Design, 2004. ICCAD-2004..

[4]  Kevin Zhang,et al.  Dual-VT SRAM cells with full-swing single-ended bit line sensing for high-performance on-chip cache in 0.13 μm technology generation , 2000, ISLPED '00.

[5]  W. Dehaene,et al.  Read Stability and Write-Ability Analysis of SRAM Cells for Nanometer Technologies , 2006, IEEE Journal of Solid-State Circuits.

[6]  Zhiyu Liu,et al.  Characterization of a Novel Nine-Transistor SRAM Cell , 2008, IEEE Transactions on Very Large Scale Integration (VLSI) Systems.

[7]  J. Meindl,et al.  The impact of intrinsic device fluctuations on CMOS SRAM cell stability , 2001, IEEE J. Solid State Circuits.

[8]  Massoud Pedram,et al.  Low-leakage SRAM design with dual V/sub t/ transistors , 2006, 7th International Symposium on Quality Electronic Design (ISQED'06).

[9]  Andreas Moshovos,et al.  Low-leakage asymmetric-cell SRAM , 2002, ISLPED '02.