Patent ID: 7966547
Filing Date: 2011-06-21
Classification: G06F

Abstract:
1. A method for operating a collection of memory cells storing binary data, the method comprising: dividing a characteristic parameter in the collection of memory cells into a plurality of characteristic parameter bands; assigning a binary multi-bit value to each of the plurality of characteristic parameter bands such that adjacent characteristic parameter bands have assigned binary multi-bit values differing by only one bit; associating a group of memory cells in the collection of memory cells to at least one parity cell, the parity cell storing a multi-bit parity value, the multi-bit parity value indicating for the group of memory cells whether the number of occurrences of binary “true” values in each bit position of stored binary multi-bit values is odd or even so that each bit position in the group of memory cells and the parity cell has an expected parity check value; converting the binary multi-bit values and the multi-bit parity value to characteristic parameter values, the characteristic parameter values being in the characteristic parameter band associated with the assigned binary multi-bit value corresponding to the binary multi-bit value; storing the binary multi-bit values and the multi-bit parity value in the group of memory cells and the parity cell; retrieving the stored characteristic parameter values from the group of memory cells and the parity cell; converting the stored characteristic parameter values to retrieved binary multi-bit values according to the assigned binary multi-bit values; calculating an actual parity check value, the actual parity check value indicating for the group of memory cells whether the number of occurrences of binary “true” values in each bit position of the retrieved binary multi-bit values is odd or even; and if the actual parity check value is not equal to the expected parity check value, the method further comprising: