A nonvolatile memory includes a plurality of N-bit multi-level cell (MLC) memory cells and a controller. The plurality of N-bit MLC memory cells are for storing N pages of data, each of the MLC memory cells programmable into any one of 2N threshold voltage distributions, where N is a positive number. The controller is configured to program the N pages of data into the MLC memory cells, and to execute a partial interleave process in which the N pages of data are divided into M page groups, where M is a positive number and where each page group includes at least one of the N pages of data, and in which each of the M page groups is applied to an error correction code (ECC) circuit to generate parity bits for the respective M page groups, where a bit-error rate (BER) among the pages within each of the M groups is equalized by the partial interleave process.