Memory redundance circuit techniques
In a memory module having a designated group of memory cells assigned to represent a logical portion of the memory structure, a memory redundancy circuit having a redundant group of memory cells; and a redundancy controller coupled with the designated group and the redundant group. The redundancy controller, which can include a redundancy decoder, assigns the redundant group to the logical portion of the memory structure in response to a preselected memory group condition, e.g., a “FAILED” memory group condition. The redundancy controller also can include selectable switches, for example, fuses, which can encode the preselected memory group condition. The designated group of memory cells and the redundant group of memory cells can be a memory row, a memory column, a preselected portion of a memory module, a selectable portion of a memory module, a memory module, or a combination thereof.
1. A memory redundancy circuit in a memory module having a designated group of memory cells assigned to represent a logical portion of the memory structure, the memory redundancy circuit comprising:
a redundant group of memory cells; and
a redundancy controller coupled with the designated group and the redundant group, the redundancy controller assigning the redundant group to the logical portion of the memory structure, responsive to a preselected memory group condition,
wherein the redundancy controller comprises redundancy decoders responsive to encoded signals representative of the preselected memory group condition in at least one of a row direction and a column direction.
2. The memory redundancy circuit according to claim 1 , wherein the encoded signals comprises an encoded address signal that is stored in a programmable address capture circuit.
3. The memory redundancy circuit according to claim 2 , wherein the programmable address capture circuit comprises a first programmable address capture circuit that stores a first encoded address representing a row group condition.
4. The memory redundancy circuit according to claim 3 , wherein the programmable address capture circuit comprises a second programmable address capture circuit that stores a second encoded address representing a column group condition.
5. The memory redundancy circuit according to claim 2 , wherein the programmable address capture circuit comprises a software programmable mode and a hardware programmable mode.
6. The memory redundancy circuit according to claim 5 , wherein the encoded address signal is loaded through a first input port interface adapted to shift in an appropriate value indicating that at least one of the memory cell groups is flawed.
7. The memory redundancy circuit according to claim 6 , comprising:
a fuse circuit operatively coupled with the programmable address capture circuit forming a parallel load register through a second input port interface and adapted to indicate that at least one of the memory cell groups is flawed.
8. A memory redundancy circuit in a memory module having a designated group of memory cells assigned to represent a logical portion of the memory structure, the memory redundancy circuit comprising:
a redundant group of memory cells; and
a redundancy controller coupled with the designated group and the redundant group, the redundancy controller assigning the redundant group to the logical portion of the memory structure, responsive to a preselected memory group condition,
wherein the redundancy circuit that is in communication with each of the designated group of memory cells and the redundant group of memory cells comprises a plurality of memory columns.
9. A memory redundancy circuit in a memory module having a designated group of memory cells assigned to represent a logical portion of the memory structure, the memory redundancy circuit comprising:
a redundant group of memory cells; and
a redundancy controller coupled with the designated group and the redundant group, the redundancy controller assigning the redundant group to the logical portion of the memory structure, responsive to a preselected memory group condition,
wherein the redundancy circuit that is in communication with each of the designated group of memory cells and the redundant group of memory cells comprises a plurality of memory rows.
10. A memory redundancy circuit in a memory module having a designated group of memory cells assigned to represent a logical portion of the memory structure, the memory redundancy circuit comprising:
a redundant group of memory cells; and
a redundancy controller coupled with the designated group and the redundant group, the redundancy controller assigning the redundant group to the logical portion of the memory structure, responsive to a preselected memory group condition,
wherein the redundant group of memory cells are selected by hierarchically activating a redundant data access circuit that is in communication with the redundant group of memory cells.
11. The memory redundancy circuit according to claim 10 , comprising:
circuitry that transfers data into and out of the redundant group of memory cells.
12. The memory redundancy circuit according to claim 11 , wherein the circuitry that transfers data into and out of the redundant group of memory cells comprises a redundant read sense amplifier and one or more associated redundant group coupling devices.
13. The memory redundancy circuit according to claim 12 , comprising:
an activation signal driven by the redundancy controller to switch in an associated redundant group of memory cells upon the redundancy controller encoding a group address signal representing a normal group of memory cells that is to be replaced.
14. The memory redundancy circuit according to claim 12 , comprising:
an activation signal driven by the redundancy controller to switch in an associated redundant group of memory cells upon the redundancy controller encoding a group address signal representing a normal group of memory cells that is to be switched out.
15. The memory redundancy circuit according to claim 12 , wherein the redundant group coupling devices comprise switches that switch in a complimentary localized bit line associated with the redundant group of memory cells to the redundant read sense amplifier.
16. The memory redundancy circuit according to claim 15 , wherein at least one of the switches of the redundant group coupling devices operatively couples a particular redundant colunm of memory cells.
17. The memory redundancy circuit according to claim 16 , wherein at least one of the switches of the redundant group coupling devices operatively couples the redundant group of memory cells.
18. The memory redundancy circuit according to claim 9 , wherein the redundancy controller comprises a redundancy decoder responsive to an encoded signal representative of the preselected memory group condition.
19. The memory redundancy circuit according to claim 9 , wherein the redundancy controller comprises a plurality of selectable switches, the plurality of selectable switches encoding the preselected memory group condition.
20. The memory redundancy circuit according to claim 19 , wherein the plurality of selectable switches comprise fuses.
21. The memory redundancy circuit according to claim 20 , wherein the preselected memory group condition is a “FAILED” memory group condition, representative of a designated group malfunction.
22. The memory redundancy circuit according to claim 9 , wherein each of the designated group of memory cells and the redundant group of memory cells comprises one of a memory row, a memory column, a preselected portion of a memory module, a selectable portion of a memory module, and a combination thereof.
23. The memory redundancy circuit according to claim 10 , wherein the redundancy controller comprises a redundancy decoder responsive to an encoded signal representative of the preselected memory group condition.
24. The memory redundancy circuit according to claim 10 , wherein the redundancy controller comprises a plurality of selectable switches, the plurality of selectable switches encoding the preselected memory group condition.
25. The memory redundancy circuit according to claim 24 , wherein the plurality of selectable switches comprise fuses.
26. The memory redundancy circuit according to claim 25 , wherein the preselected memory group condition is a “FAILED” memory group condition, representative of a designated group malfunction.
27. The memory redundancy circuit according to claim 10 , wherein each of the designated group of memory cells and the redundant group of memory cells comprises one of a memory row, a memory column, a preselected portion of a memory module, a selectable portion of a memory module, and a combination thereof.