Opportunistic Refreshing Algorithm for eDRAM Memories

Embedded DRAM (eDRAM) is an alternative technology that can replace the area and power consumed by SRAM cache memories. eDRAM consumes half the area and an order of magnitude less power than SRAM, but has the drawback of access blockage caused by its periodic data refreshing. This paper presents an opportunistic refreshing algorithm along with the appropriate memory architecture and skim control logic. This architecture takes advantage of the access idleness of the internal partitions of the memory and enables most of the refreshing operations to run concurrently with the ordinary R/W access. This eliminates the refreshing burden almost completely. The algorithm was simulated with industrial DSP access traces, and outperformed in a wide range of eDRAM technologies and internal memory architectures.