US 6,747,910 B2Granted

Thin film magnetic memory device for selectively supplying a desired data write current to a plurality of memory blocks

AssigneeRenesas Technology Corp.

InventorTakaharu Tsuji

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Abstract

Each of N memory blocks of first to Nth stages includes a plurality of first and second driver units. The plurality of first and second driver units are respectively provided corresponding to one end and another end of a plurality of digit lines included in each memory block. Each of the first driver units in memory blocks before a selected memory block connects a corresponding digit line to a first voltage according to a voltage level on a digit line of the same row in a memory block of a previous stage. A second driver unit in the selected memory block connects a corresponding digit line to a second voltage in order to supply a data write current. In other words, digit lines in the memory blocks before the selected memory block are not used as current lines but as signal lines.

Claims20

Dependent claims

A thin film magnetic memory device, comprising:

a plurality of magnetic memory cells arranged in a matrix, wherein
said plurality of magnetic memory cells being divided into N memory blocks of first to Nth stages along a row direction so that said N memory blocks share memory cell rows (where N is a natural number),
said thin film magnetic memory device further comprising in each of said memory blocks:
a plurality of digit lines provided corresponding to the memory cell rows, respectively, for selectively supplying a data write current for generating a data write magnetic field to the magnetic memory cell selected for data write operation;
a plurality of first driver units provided corresponding to said plurality of digit lines, respectively, and each controlling connection between one end of the corresponding digit line and a first voltage;
and
a plurality of second driver units provided corresponding to said plurality of digit lines, respectively, and each controlling connection between another end of said corresponding digit line and a second voltage, wherein
in said data write operation, each of said first driver units corresponding to the memory block of the first stage connects said one end of the corresponding digit line to said first voltage according to a row selection result,
in said data write operation, each of said second driver units corresponding to the memory block of the Ith stage including the selected magnetic memory cell (where I is a natural number satisfying I≦N) connects said another end of the corresponding digit line to said second voltage according to a selection result of said N memory blocks,
when I≧2 in said data write operation, each of said first driver units corresponding to each of the memory blocks of the second to Ith stages connects said one end of the corresponding digit line to said first voltage according to a voltage level on the digit line of the same memory cell row in the memory block of a previous stage, and
when I≧2 in said data write operation, each of said second driver units corresponding to each of the memory blocks of the first to (I−1)th stages disconnects said another end of the corresponding digit line from said second voltage according to said selection result of said N memory blocks.

8 more elements

A thin film magnetic memory device, comprising:

a plurality of magnetic memory cells arranged in a matrix;
a plurality of digit lines provided corresponding to the memory cell rows, respectively, for selectively supplying a data write current for generating a data write magnetic field to the magnetic memory cell selected for data write operation;
a plurality of first driver units provided corresponding to said plurality of digit lines, respectively, and each controlling connection between one end of the corresponding digit line and a first voltage;
a plurality of second driver units provided corresponding to said plurality of digit lines, respectively, and each controlling connection between another end of said corresponding digit line and a second voltage;
a plurality of word lines provided corresponding to said memory cell rows;
and
a plurality of driving sections provided corresponding to said plurality of word lines, respectively, and each activating the corresponding word line according to a voltage level of the digit line of the same row, wherein
in said data write operation, each of said first driver units connects said one end of said corresponding digit line to said first voltage according to a row selection result, and each of said second driver units connects said another end of said corresponding digit line to said second voltage, and
in said data read operation, each of said first driver units connects said one end of said corresponding digit line to said first voltage according to a row selection result, and each of said second driver units disconnects said another end of said corresponding digit line from said second voltage.

6 more elements

A thin film magnetic memory device, comprising:

a plurality of magnetic memory cells arranged in a matrix;
a plurality of digit lines provided corresponding to the memory cell rows, respectively, for selectively supplying a first data write current to the magnetic memory cell selected for data write operation;
a plurality of bit lines provided corresponding to the memory cell columns, respectively, for selectively supplying a second data write current to said magnetic memory cell selected for said data write operation;
and
a plurality of current supply circuits provided corresponding to said plurality of digit lines, respectively, and each controlling supply of said first data write current to the corresponding digit line, wherein
in said data write operation, each of said current supply circuits supplies said first data write current to said corresponding digit line according to a row selection result,
in test operation, each of said current supply circuits supplies said first data write current which is smaller than that supplied in said data write operation, and
in said test operation, at least one of said plurality of bit lines receives said second data write current.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/334,713Filed 2 Jan 2003
Priority: JP 2002-0269454 Feb 2002
Published: US 2003/0147274 A17 Aug 2003
Granted: 8 Jun 2004
Term ends: Not estimatedThe source records don’t support an estimate.

Classification13 codes

G11C 11/15
Using thin-film elements: using multiple magnetic layers
G11C 11/1675
Auxiliary circuits: writing or programming circuits or methods
G11C 5/025
Disposition of storage elements, e.g. in the form of a matrix array: geometric lay-out considerations of storage- and peripheral-blocks in a…
G11C 7/02
Arrangements for writing information into, or reading information out from, a digital store: with means for avoiding parasitic signals