PARTIAL REFRESH FOR SYNCHRONOUS DYNAMIC RANDOM ACCESS MEMORY (SDRAM) CIRCUITS

摘要

A semiconductor dynamic random access memory (DRAM) 300 with a programmable memory refresh counter 345 is presented. The counter 345 permits the specification of portions of the DRAM 300 to be refreshed, saving power and time over DRAMs that refresh the entire memory. The counter 345 may be programmed with a wordline address at the beginning of a block of memory and subsequent refresh operations automatically increment or decrement the value in the counter. Additionally, blocks of the memory not being refreshed can be accessed (written or read), improving the utilization of the memory device.