Patent ID: 8966342
Filing Date: 2015-02-24
Classification: G06F,G11C,H03M

Abstract:
1. A method of reading a plurality of data bits that are stored in a memory that includes a plurality of multi-bit cells, the storing being effected by computing a plurality of protected bits that correspond to the data bits and then storing the protected bits in the cells of the memory, the method comprising: (a) reading the cells, thereby obtaining a plurality of read protected bits; and (b) recovering the data bits from the read protected bits, wherein said recovering is performed based at least in part on a priori estimates of respective probabilities of at least two of said read protected bits being erroneous, wherein said a priori estimates are independent of values of said read protected bits, wherein said a priori estimates are initial values determined prior to reading the values of said read protected bits, wherein at least one said estimate is different from at least one other said estimate, and wherein said a priori estimates are determined based at least in part on a position of respective significances of said read bits relative to a voltage state distribution of respective multi-bit cells storing said read bits.