Patent ID: 9722635
Date: 2017-08-01
CPC Classifications: G06F,G11C,H03M

Claim:
1. A controller for a solid state drive, wherein the solid state drive comprises memory cells each one for storing a symbol among a plurality of possible symbols that the memory cell is designed to store, and wherein the controller comprises: an encoding unit for encoding information bits into encoded bits; a mapping unit for mapping the encoded bits into said symbols, wherein said symbols are determined based on a plurality of allowed symbols that the memory cells are allowed to store, said plurality of allowed symbols being a subset of the plurality of the possible symbols such that a plurality of forbidden symbols not allowed to be stored in the memory cells are defined among the plurality of the possible symbols, a demapping unit for demapping read symbols and for providing an indication of the reliability of the read symbols based on said plurality of forbidden symbols, and a soft decoding unit for soft decoding the read symbols according to said indication of the reliability of the read symbols thereby obtaining said information bits.