A 4-Mb 0.18-μm 1T1MTJ toggle MRAM with balanced three input sensing scheme and locally mirrored unidirectional write drivers

Author

Andre, Thomas W. ; Nahas, Joseph J. ; Subramanian, Chitra K. ; Garni, Bradley J. ; Lin, Halbert S. ; Omair, Asim ; Martino, William L., Jr.

Author_Institution

Freescale Semicond., Austin, TX, USA

Volume

40

Issue

1

fYear

2005

Firstpage

301

Lastpage

309

Abstract

A 4-Mb toggle MRAM, built in 0.18-μm five level metal CMOS technology, uses a 1.55 μm² bit cell with a single toggling magneto tunnel junction to achieve a chip size of 4.5 mm × 6.3 mm. The memory uses unidirectional programming currents controlled by locally mirrored write drivers to apply a robust toggle write sequence. An isolated read architecture driven by a balanced three input current mirror sense amplifier supports 25-ns cycle time asynchronous operation.

Keywords

CMOS memory circuits; asynchronous circuits; magnetic storage; magnetoresistive devices; memory architecture; random-access storage; tunnelling magnetoresistance; 0.18 micron; 1T1MTJ toggle MRAM; 25 ns; 4 MB; 4.5 mm; 6.3 mm; balanced three input sensing scheme; current mirror sense amplifier; magnetic memories; magnetoresistance; memory architecture; read architecture; single toggling magneto tunnel junction; unidirectional programming currents; unidirectional write drivers; CMOS technology; Conductors; Isolation technology; Magnetic fields; Magnetic switching; Magnetic tunneling; Manufacturing; Memory architecture; Space technology; Switches; MRAM; magnetic memories; magnetoresistance; memory architecture;

fLanguage

English

Journal_Title

Solid-State Circuits, IEEE Journal of

Publisher

ieee

ISSN

0018-9200

Type

jour

DOI

10.1109/JSSC.2004.837962

Filename

1375014