A memory power optimization technique for application specific embedded systems
In this paper, a novel application specific power optimization technique utilizing small instruction ROM which is placed between an instruction cache or a main program memory and CPU core is proposed. Our optimization technique targets embedded systems which assume the following: ii instruction memories are organized by two on-chip memories, a main program memory and a subprogram memory, (ii) these two memories can he independently powered-up or powered-down by a special instruction of a core processor, and (iii) a compiler optimizes an allocation of object code into these two memories so as to minimize average of read energy consumption. In many application programs, only a few basic blocks are frequently executed. Therefore, allocating these frequently executed basic blocks into low power subprogram memory leads significant energy reduction. Our experiments with actual ROM (Read Only Memory) modules created with 0.5 mu m CMOS process technology, and MPEG2 codec program demonstrate significant energy reductions up to more than 50% at best case over the previous approach that applies only divided bit and word lines structure.
memory embedded system low power design hardware/software codesign