US Patent 9318166 Systems and methods of storing data

A method of reading data in a data storage device with a controller and a memory includes generating, in the memory, a set of bits corresponding to a particular storage element of the memory. The set of bits indicates a group of threshold voltage intervals. A threshold voltage of the particular storage element corresponds to one of the threshold voltage intervals within the group. At least one threshold voltage interval within the group is separated from another threshold voltage interval within the group by an intervening threshold voltage interval that is not within the group. The method also includes sending the set of bits to the controller. The set of bits includes a first hard bit that corresponds to a value read from the particular storage element and a first soft bit that corresponds to a reliability measure.