Title :
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
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;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2004.837962
