An object is to realize high-capacity of a memory while reducing power
consumption and making the power consumption even throughout the memory.
A memory includes a plurality of memory block arranged to be
symmetrically to each other. Also, a specific combination of signals
among address signals supplied to the memory, a memory block including a
memory cell to be read from or written to is specified. Further, signals
supplied to other memory blocks than the above memory block is maintained
at a constant value. Consequently, a wiring length of a bit line in a
memory array can be shortened, and current consumption can be made to be
even among data reading or writing from/to memory cells of a variety of
addresses within the memory, at the same time as reducing load
capacitance.