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.