Multi-level cell memory devices using trellis coded modulation and methods of storing data in and reading data from the memory devices

A method of storing data in a multi-level cell (MLC) memory device, the method comprising:

• encoding data using a first encoding scheme to generate an outer encoded bit stream;
• and
• applying a program pulse to a MLC memory cell of the MLC memory device to write the data in the MLC memory cell;
• generating a demapped bit stream by demapping an output pulse from the MLC;
• generating an inner decoded bit stream by Viterbi decoding the demapped bit stream,
• wherein the program pulse is generated by Trellis coded modulation of the outer encoded bit stream.

A method of reading data from a multi-level cell (MLC) memory device, the method comprising:

• receiving an output pulse from a MLC memory cell of the MLC memory device;
• generating an inner decoded bit stream from the output pulse in response to application of a read signal;
• generating a demapped bit stream by demapping the output pulse;
• and
• generating the inner decoded bit stream by Viterbi decoding the demapped bit stream.