Error correction decoder and operation method of the error correction decoder

An error correction decoder configured to correct an error of data read from a nonvolatile memory comprising:

• a syndrome calculation unit configured to receive the data and calculate syndromes based on the received data;
• a key equation solving unit configured to receive the syndromes and calculate an error location polynomial by performing a simplified error correction based on the received syndromes when a mode signal indicates a simplified mode and performing a full error correction based on the received syndromes when the mode signal indicates a full mode;
• a chien search unit configured to receive the error location polynomial and generate error location information by performing a chien search based on the received error location polynomial;
• an error correction unit configured to receive the error location information and correct an error of the received data based on the received error location information;
• and
• a control unit configured to control the mode signal.

An error correction method, comprising:

• receiving data;
• performing a first error correction with respect to the received data in a simplified mode, the performing a first error correction including,
• calculating syndromes based on the received data,
• performing a calculation loop of calculating a first error location polynomial with respect to a selected one of the syndromes, and
• repeating the performing a calculation loop until a number of times that a selected one of the syndromes belongs to the first error location polynomial of a previous calculation loop reaches a threshold number;
• and
• performing a second error correction of the received data in a full mode when the first error correction is terminated early without completely performing the repeating with respect to respective syndromes.