Powering DDR memory and SSTL

摘要

Most modern electronics require some form of DRAM. By far, the most common DRAM is SSTL (stub-series-terminated-logic)-driven DDR (double-data-rate) memory. Conventional logic and I/Os use standard system bus voltages; however, DDR-memory devices need the precision that only local POL (point-of-load) regulators can provide. For sufficient noise margin, two of the five system supply voltages must reference other voltages.