Back to results
US 2004/0165419 A1Published application
Magnetic memory device with reference cell for data reading
AssigneeRenesas Technology Corp.
InventorTakaharu Tsuji
Life of this patent
Estimating the term…
Abstract
In a normal data reading, one of word lines and one of first and second dummy word lines are selected and data is read out through the access to selected regular memory cell and a reference cell. In a test mode, each of word lines are turned to a non-select state and both of first and second dummy word lines are selected and by setting one of first and second reference voltages to a level different from a level during the normal data reading, data is read out through the access to the reference cells.
Claims10
A magnetic memory device comprising:
- a plurality of word lines and a plurality of dummy word lines arranged along a same direction;
- a plurality of bit line pairs each formed with a first and second bit lines arranged in a direction perpendicular to the direction of said plurality of word lines and said plurality of dummy word lines;
- a plurality of magnetic memory cells alternately arranged at intersections of said plurality of word lines and said first and second bit lines, and electrically connected with the corresponding first or second bit line in response to a selection of the corresponding word line;
- a plurality of magnetic reference cells alternately arranged at intersections of said plurality of dummy word lines and said first and second bit lines, and electrically connected to the corresponding said first or second bit line in response to a selection of the corresponding dummy word line;
- a data reading circuit performing a data reading based on a passing current of said first and second bit lines forming same said bit line pair;
- and
- a row select unit controlling a selection of said plurality of word lines and said plurality of dummy word lines according to an address signal,
- wherein said row select unit selects one of said plurality of word lines and one of said plurality of dummy word lines in a normal data reading such that said first and second bit lines forming each of said bit line pairs are connected to one of said plurality of magnetic memory cells and one of said plurality of magnetic reference cells, respectively, and sets each of said plurality of word lines to a non-select state and at the same time selects said plurality of dummy word lines in a first test mode such that said first and second bit lines forming each of said bit line pairs are connected to two of said plurality of magnetic reference cells, respectively.
5 more elements
Dependencies are inferred from the claim text.