ENCODING METHOD AND MEMORY DEVICE

摘要

A memory device such as a flash memory for multiple-bit recording. In a flash memory (10) for 4-bit recording, a write operation is carried out by converting input data (Din) to a reduced Reed-Solomon code by an encoder (12) to provide a write data (WD), converting the write data to 4-bit parallel data by a converter (13), and supplying the converted data to a cell array (11) to write individual memory cells. A read operation is carried out by converting data (RD) read from the cell array (11) into 1-byte parallel data (8 bits) by a converter (14), and supplying the parallel data to a decoder (15) where error correcting is performed byte by byte to provide output data (Dout). The use of the Reed-Solomon code results in good performance with a smaller number of error corrections.