US Patent 9825651 Controller, semiconductor memory system and operating method thereof

An operating method of a controller includes: a first step of generating an internal codeword including an ECC unit data and an internal parity code by performing ECC decoding operation to an input data; a second step of updating an external parity code based on the ECC unit data, which is included in the internal codeword currently generated, and the ECC unit data, which is included in the internal codeword previously generated; and a third step of storing in a semiconductor memory device one or more internal codewords and the updated external parity code, which are generated through repetition of the first and second steps, by a unit of predetermined storage size.