Semiconductor memory system having ECC circuit and controlling method thereof

摘要

A semiconductor memory system includes a memory area and an error-correcting (ECC) circuit. The memory area includes a plurality of cells, and the ECC circuit is configured to determine whether uncorrectable error data exists or not by using a parity according to cell data of the memory area in a read mode and a parity according to an encoding result of corrected data of the cell data.