A Mechanism for Dependence of Refresh Time on Data Pattern in DRAM

We measured the refresh time (tREF) according to data patterns for several dynamic random access memory (DRAM) chips. The measured tREF depends on the cell data pattern; moreover, these have their own dependences, which differ for several DRAM chips. We analyzed these phenomena in terms of both refresh and offset measurements, and our novel result was that tREF dependence on data patterns is determined by both a cell leakage mechanism and an offset by sensing noise.