A memory device and method for selectable sub-array activation. In one preferred
embodiment, a memory array is provided comprising a plurality of groups of sub-arrays
and circuitry operative to simultaneously write data into and/or read data from
a selected number of groups of sub-arrays. By selecting the number of groups of
sub-arrays into which data is written and/or from which data is read, the write
and/or read data rate is varied. Such varying can be used to prevent thermal run-away
of the memory array. Other preferred embodiments are provided, and each of the
preferred embodiments can be used alone or in combination with one another.
