What is refresh rate and self refresh?
A memory module is made up of electrical cells. The refresh process recharges these cells, which are arranged on the chips in rows. The refresh cycle refers to the number of rows that must be refreshed. The common refresh cycles are 2K, 4K and 8K. Refresh cycle together with refresh period determines how often refresh is needed, which is defined as Refresh Rate. For the same refresh period, 4K refresh parts needs to be refreshed more frequently than 2K parts. For the same size DRAM, 4K refresh part consume less power than 2K refresh parts. Some specially design DRAMs feature self refresh technology, which enables the components to refresh on their own — independent from the CPU or external refresh circuits.
