System and method for sensing memory cells of an array of memory cells

• US 6,765,834 B2
• Filed: 11/19/2002
• Issued: 07/20/2004
• Est. Priority Date: 11/19/2002
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Perner, Frederick
• Primary Examiner(s): TRAN, MICHAEL THANH
• Application Number:
  US10/299,288
• Publication Number:
  US 20040095826A1
• Time in Patent Office: 609 Days
• Field of Search: 365/209, 365/205, 365/129
• US Class Current: 365/209
• CPC Class Codes: G11C 11/16 using elements in which the storage effect is based on magnetic spin effect
• CPC Class Codes: G11C 7/06 Sense amplifiers; Associated circuits , e.g. timing or triggering circuits

Abstract

The invention includes a memory cell array sensing system. The memory cell array sensing system includes an array of memory cells located on a first plane of an integrated circuit. The array of memory cells includes groups of memory cells, wherein each group corresponds to a range of rows of the memory cells. A plurality of sense amplifiers located on a sense plane that is adjacent to the first plane, at least one sense amplifier being associated with each group. Multiple memory cells are simultaneously sensed by electrically connecting the multiple memory cells to sense amplifiers belonging to groups associated with the multiple memory cells, and to sense amplifiers not belonging to the groups associated with the multiple memory cells. A method of the invention includes electrically connecting multiple memory cells to sense amplifiers belonging to groups associated with the multiple memory cells, and to sense amplifiers not belonging to the groups associated with the multiple memory cells; and sensing logic states of the multiple memory cells.

Claims

1. A memory cell array sensing system comprising:

an array of memory cells located on a first plane of an integrated circuit, the array of memory cells comprising groups of memory cells, wherein each group corresponds to a range of rows of the memory cells;

a plurality of sense amplifiers located on a sense plane that is adjacent to the first plane, at least one sense amplifier being associated with each group, wherein no memory cells are located on the sense plane;

wherein multiple memory cells are simultaneously sensed by electrically connecting the multiple memory cells to sense amplifiers belonging to groups associated with the multiple memory cells.

2. The memory cell array sensing system of claim 1, wherein a sense amplifier is associated with a group of memory cells if the sense amplifier is located directly adjacent to the group of memory cells.

3. The memory cell array sensing system of claim 1, wherein a sense amplifier is associated with a group of memory cells if the sense amplifier is one of the plurality of sense amplifiers that is physically located the closest to the group of memory cells.

4. The memory cell array sensing system of claim 1, wherein the array of memory cells are arranged in rows and columns.

5. The memory cell array sensing system of claim 4, wherein a single word line selects a single row from a selected group of memory cells.

6. The memory cell array sensing system of claim 1, wherein the multiple memory cells are simultaneously sensed through a plurality of bit lines.

7. The memory cell array sensing system of claim 6, wherein the plurality of bit lines are electrically connected to sense amplifiers that are associated with groups of the sensed memory cells, and electrically connected to sense amplifiers that are not associated with groups of the sensed memory cells.

8. The memory cell array sensing system of claim 4, wherein the multiple memory cells are simultaneously sensed by electrically connecting the multiple memory cells to sense amplifiers through input lines that extend along the columns of memory cells, and are connectable between the multiple memory cells and the sense amplifiers.

9. The memory cell array sensing system of claim 7, wherein the inputs lines extend across multiple groups of memory cells, and across multiple sense amplifiers.

10. The memory cell array sensing system of claim 1, wherein a memory cell group area of the first plane is occupied by a group of memory cells, the memory cell group area being defined by a physical pitch between rows of the memory cells.

11. The memory cell array sensing system of claim 10, wherein a sense amplifier area occupied by each sense amplifier of the sense plane, is approximately equal to the memory cell group area occupied by the group of memory cells.

12. The memory cell array sensing system of claim 11, wherein the sense amplifier area of a sense amplifier associated with a group is adjacent to the memory cell group area of the group of memory cells within the same group.

13. The memory cell array sensing system of claim 1, wherein each sense amplifier is connectable to at least one column of memory cells through a selectable multiplexer.

14. A method of sensing a state of a selected memory cells within a memory cell array sensing system, the memory cell array sensing system comprising an array of memory cells located on a first plane of an integrated circuit, the array of memory cells comprising groups of memory cells, wherein each group corresponds to a range of rows of the memory cells, the memory cell array sensing system further comprising a plurality of sense amplifiers located on a sense plane that is adjacent to the first plane, at least one sense amplifier being associated with each group, wherein no memory cells are located on the sense plane, the method comprising:

electrically connecting the multiple memory cells to sense amplifiers belonging to groups associated with the multiple memory cells; and

sensing logic states of the multiple memory cells.

15. The method of sensing a state of a selected memory cells of claim 14, wherein the multiple memory cells are electrically connected to the sense amplifier through input lines that extend along the columns of memory cells, and are connectable between the multiple memory cells and the sense amplifiers.

16. An MRAM memory comprising:

an array of MRAM cells comprising rows and columns of MRAM cells located on a first plane of an integrated circuit, the array of MRAM cells comprising groups of MRAM cells, wherein each group corresponds to a range of rows of the MRAM cells;

a plurality of sense amplifiers located on a sense plane that is adjacent to the first plane, at least one sense amplifier being associated with each group, wherein no MRAM cells are located on the sense plane;

wherein multiple MRAM are simultaneously sensed by electrically connecting the multiple memory cells to sense amplifiers belonging to groups associated with the multiple memory cells.

17. The MRAM memory of claim 16, wherein a sense amplifier is associated with a group of MRAM cells if the sense amplifier is located directly adjacent to the group of MRAM cells.

18. The MRAM memory of claim 16, wherein a sense amplifier is associated with a group of MRAM cells if the sense amplifier is a one of the plurality of sense amplifiers that is physically located closest to the group of MRAM cells.

19. A computer system comprising:

a central processing unit;

MRAM memory connected to the central processing unit, the MRAM memory comprising;

an array of MRAM cells comprising rows and columns of MRAM cells located on a first plane of an integrated circuit, the array of MRAM cells comprising groups of MRAM cells, wherein each group corresponds to a range of rows of the MRAM cells;

a plurality of sense amplifiers located on a sense plane that is adjacent to the first plane, at least one sense amplifier being associated with each group, wherein no memory cells are located on the sense plane;

wherein multiple MRAM are simultaneously sensed by electrically connecting the multiple memory cells to sense amplifiers belonging to groups associated with the multiple memory cell.

20. The computer system of claim 19, wherein a sense amplifier is associated with a group of MRAM cells if the sense amplifier is located directly adjacent to the group of MRAM cells.

21. The computer system of claim 19, wherein a sense amplifier is associated with a group of MRAM cells if the sense amplifier is a one of the plurality of sense amplifiers that is physically located the closest to the group of MRAM cells.