R-MRAM: A ROM-Embedded STT MRAM Cache

Author

Dongsoo Lee ; Xuanyao Fong ; Roy, Kaushik

Author_Institution

Sch. of Electr. & Comput. Eng., Purdue Univ., West Lafayette, IN, USA

Volume

34

Issue

10

fYear

2013

fDate

Oct. 2013

Firstpage

1256

Lastpage

1258

Abstract

We present a new spin-transfer torque magnetic random access memory (STT MRAM) bit-cell that is embedded with read-only memory (ROM) functionality. The proposed ROM-embedded STT MRAM (R-MRAM) bit-cells include one extra bit-line. ROM data is stored by selectively connecting the magnetic tunnel junction (MTJ) to one of the two bit-lines. For normal RAM-mode operations, both bit-lines are driven and sensed to switch and read the MTJ state. When reading ROM data, only one read current source is turned on and the corresponding sense amplifier is used to monitor which bit-line is connected to the bit-cell (the MTJ state can be ignored).

Keywords

MRAM devices; amplifiers; embedded systems; magnetic tunnelling; read-only storage; MTJ state; R-MRAM; RAM-mode operations; ROM data; ROM functionality; ROM-embedded STT MRAM cache; STT MRAM bit-cell; bit-line; magnetic tunnel junction; read current source; read-only memory; sense amplifier; spin-transfer torque magnetic random access memory; Capacitance; Magnetic tunneling; Random access memory; Read only memory; Sensors; Torque; Transistors; Cache design; ROM-embedded STT MRAM; read-only memory (ROM); spin-transfer torque magnetic random access memory (STT MRAM);

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2013.2279137

Filename

6594809