Static type semiconductor memory device that can suppress standby current

• US 6,333,877 B1
• Filed: 06/29/2000
• Issued: 12/25/2001
• Est. Priority Date: 01/13/2000
• Status: Expired due to Term

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Akai, Kiyoyasu, Nagaoka, Hideaki
• Primary Examiner(s): Ho, Hoai V.
• Application Number:
  US09/606,316
• Time in Patent Office: 544 Days
• Field of Search: 365/200, 365/154, 365/226, 365/129, 365/189.01, 365/225.7
• US Class Current: 365/200
• CPC Class Codes: G11C 29/70 Masking faults in memories by using spares or by reconfiguring

Abstract

A memory cell power supply line is provided to supply a ground potential corresponding to each column in a regular memory cell array. Among fuse elements, the fuse element corresponding to the memory cell column that is to be subjected to redundancy replacement is decoupled, whereby supply of the ground potential to the regular memory cell column to be replaced is suppressed.

Claims

1. A static type semiconductor memory device comprising:

a regular memory cell array in which a plurality of memory cells are arranged in a matrix, each memory cell capable of retaining a first level and a second level,

said regular memory cell array being divided in a plurality of memory cell replacement units;

a redundant memory cell array for redundancy repair for one of said memory cell replacement units in said regular memory cell array;

a power supply node to which a first potential corresponding to said first level is supplied;

a plurality of first lines, provided corresponding to said memory cell replacement units respectively, each for supplying said first potential from said power supply node to said memory cells in a corresponding said memory cell replacement unit; and

a potential supply control circuit that can selectively cease supply of said first potential from said power supply node to one of said plurality of first lines;

wherein said power supply control circuit comprises a potential modify circuit that can modify the potential supplied to said plurality of first lines to a second potential corresponding to said second level from said first potential independently and in a nonvolatile manner.

2. The static type semiconductor memory device according to claim 1, wherein said redundant memory cell array is divided into redundancy replacement units, each including memory cells identical in number to said memory cell replacement unit,

wherein said potential modify circuit comprises

a plurality of nonvolatile storage circuits provided corresponding to said memory cell replacement units, respectively, to set redundancy replacement of a corresponding said memory cell replacement unit, and

a plurality of potential set circuits provided corresponding to said nonvolatile storage circuits, respectively, to modify the potential supplied to a corresponding first line out of said plurality of first lines to said second potential from said first potential according to stored information of said nonvolatile storage circuit,

said static type semiconductor memory device further comprising a redundancy select circuit selecting said redundancy replacement unit instead of said memory cell replacement unit that is to be subjected to redundancy replacement according to stored information in said nonvolatile storage circuit when said memory cell replacement unit to be subjected to redundancy replacement is selected according to an external address signal.

3. The static type semiconductor memory device according to claim 2, wherein each of said nonvolatile storage circuits includes a fuse element that can be decoupled to set redundancy replacement of said corresponding memory cell replacement unit,

wherein each of said potential set circuit modifies the potential supplied to said first line according to whether said fuse element included in a corresponding nonvolatile storage circuit out of said plurality of nonvolatile storage circuits is decoupled or not.

4. The static type semiconductor memory device according to claim 1, wherein said first potential is lower than said second potential, and each said memory cell redundancy unit includes a memory cell row.

5. The static type semiconductor memory device according to claim 1, wherein said first potential is lower than said second potential, and each said memory cell replacement unit includes a memory cell column.

6. The static type semiconductor memory device according to claim 1, wherein each said memory cell replacement unit includes a plurality of memory cell rows.

7. The static type semiconductor memory device according to claim 1, wherein each said memory cell replacement unit includes a plurality of memory cell columns.

8. The static type semiconductor memory device according to claim 5, further comprising:

a plurality of bit line pairs provided corresponding to a column of said memory cell array, and

a plurality of bit line load circuits provided corresponding to said each bit line pair,

wherein the potential supplied to said bit line load circuit corresponding to said memory cell replacement unit that is to be replaced is set to an inactive potential in response to the potential supplied to said corresponding first line modified to said second potential from said first potential by said potential set circuit according to stored information in said nonvolatile storage circuit.

9. A static type semiconductor memory device comprising:

a regular memory cell array in which a plurality of memory cells are arranged in a matrix, each memory cell capable of retaining a first level and a second level,

said regular memory cell array being divided into a plurality of memory cell replacement units;

a redundant memory cell array to perform redundancy repair for one of said memory cell replacement units in said regular memory cell array;

a power supply node to which a first potential corresponding to said first level is supplied;

a plurality of first lines provided corresponding to said memory cell replacement units respectively, each for supplying said first potential from said power supply node to said memory cells in a corresponding one of said memory cell replacement units in a normal operation;

and a plurality of potential retain circuits provided corresponding to said plurality of first lines, respectively, each for precharging a corresponding one of said first lines to a second potential corresponding to said second level after initiation of power supply to said static type semiconductor memory device, and supplying said first potential to said corresponding one of first lines in response to said corresponding memory cell replacement unit being accessed.

10. The static type semiconductor memory device according to claim 9, further comprising:

a nonvolatile storage circuit to store in a nonvolatile manner an address corresponding to a memory cell replacement unit that is to be replaced by said redundant memory cell replacement unit out of said regular memory cell array, and

a circuit accessing said redundant memory cell array instead of said memory cell replacement unit to be replaced when selection of said memory cell replacement unit to be replaced is specified according to an address signal.

11. The static type semiconductor memory device according to claim 9, wherein each said plurality of potential retain circuits comprises

a latch circuit retaining said first potential or said second potential level according to external setting,

a precharge circuit retaining said second potential in said latch circuit after initiation of power supply to said static type semiconductor memory device, and

a potential convert circuit setting a potential level retained at said latch circuit to said first potential from said second potential according to said corresponding memory cell replacement unit being accessed,

wherein the potential level retained by said latch circuit is applied to said corresponding first line.

12. The static type semiconductor memory device according to claim 11, further comprising a circuit that accesses said memory cell replacement unit while scanning after initiation of power supply to said static type semiconductor memory device.

13. The static type semiconductor memory device according to claim 9, wherein each of said plurality of potential retain circuits comprises a latch circuit retaining a level of said first potential or second potential according to external setting,

wherein said latch circuit includes first and second inversion circuits having input nodes and output nodes connect to each other,

wherein a logic threshold value of said first and second inversion circuits are set to have said second potential retained in said latch circuit after initiation of power supply to said static type semiconductor memory device,

further comprising a potential convert circuit setting the potential level retained in said latch circuit to said first potential from said second potential according to said corresponding memory cell replacement unit being accessed,

wherein the potential level retained by said latch circuit is applied to said corresponding first line.

14. The static type semiconductor memory device according to claim 13, further comprising a circuit that accesses said memory cell replacement unit while scanning after initiation of power supply to said static type semiconductor memory device.