Semiconductor memory devices, memory systems and methods of operating semiconductor memory devices

Abstract

A semiconductor memory device includes a memory cell array, an error correction code (ECC) engine, an input/output (I/O) gating circuit and a control logic circuit. The memory cell array includes bank arrays, each of the bank arrays includes a first sub array and a second sub array, and each of the first sub array and the second sub array includes a normal cell region to store data bits and a parity cell region to store parity bits. The ECC engine generates the parity bits and corrects error bit. The I/O gating circuit is connected between the ECC engine and the memory cell array. The control logic circuit controls the I/O gating circuit to perform column access to the normal cell region according to a multiple of a burst length and to perform column access to the parity cell region according to a non-multiple of the burst length partially.