Dynamic error monitor and repair
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsHiroki Noguchi, Ku-Feng Lin, Yih Wang
Life of this patent
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Abstract
A memory device includes: a memory cell array comprising a plurality of memory cells, the plurality of memory cells comprising a plurality of data memory cells including a first data memory cell and a plurality of backup memory cells including a first backup memory cell; a storage storing an error table configured to record errors in the plurality of data memory cells, the error table including a plurality of error table entries, each error table entry corresponding to one of the plurality of data memory cell and having an address and a failure count; and a controller configured to replace the first data memory cell with the first backup memory cell based on the error table.
Claims20
A memory device, comprising:
- a memory cell array comprising a plurality of memory cells including a plurality of data memory cells actively used for storing data and a plurality of backup memory cells not actively used for storing data;
- a storage storing an error table configured to record errors associated with the plurality of data memory cells, the error table including a plurality of error table entries, each error table entry corresponding to one of the plurality of data memory cells and having an address and a failure count;
- and
- a controller configured, in response to determining from the error table that the failure count of a data memory cell is higher than a threshold failure count, to:
- transfer data stored in the data memory cell to a backup memory cell;
- designate the data memory cell as a deactivated data memory cell belonging to the plurality of backup memory cells not actively used for storing data;
- and
- designate the backup memory cell as an activated data memory cell belonging to the plurality of data memory cells actively used for storing data.
A memory device, comprising:
- a memory cell array comprising a plurality of memory cells including a plurality of data memory cells actively used for storing data and M backup memory cells not actively used for storing data, M being an integer greater than one;
- a storage storing a repair table, wherein the repair table includes M repair table entries, each repair table entry corresponding to a former data memory cell replaced by a backup memory cell and changed to a deactivated data memory cell belonging to the plurality of backup memory cells not actively used for storing data, each repair table entry having an address and a failure count;
- and
- a controller configured, in response to determining that a repair table entry has a failure count lower than a failure count of a data memory cell, to:
- designate a deactivated data memory cell associated with the repair table entry as a restored data memory cell belonging to the plurality of data memory cells actively used for storing data;
- designate the data memory cell as a deactivated data memory cell belonging to the plurality of backup memory cells not actively used for storing data;
- and
- update the repair table entry to indicate an address and the failure count of the data memory cell.
A method, comprising:
- providing a memory cell array comprising a plurality of memory cells including a plurality of data memory cells actively used for storing data and a plurality of backup memory cells not actively used for storing data;
- detecting errors in the plurality of data memory cells by an ECC circuit;
- generating an error table, the error table including a plurality of error table entries, each error table entry corresponding to one of the plurality of data memory cells cell and having an address and a failure count;
- and
- in response to determining from the error table that the failure count of a data memory cell is higher than a threshold failure count:
- transferring data stored in the data memory cell to a backup memory cell;
- designating the data memory cell as a deactivated data memory cell belonging to the plurality of backup memory cells not actively used for storing data;
- and
- designating the backup memory cell as an activated data memory cell belonging to the plurality of data memory cells actively used for storing data.
The method of 17, wherein the memory device is one of:
- a ferroelectric random access memory (FRAM) device, a magnetic random access memory (MRAM) device, a resistive random access memory (RRAM) device, and a phase-change memory (PCM) device.
Dependencies are inferred from the claim text.