Patent ID: 8531888

Claim:
A system comprising: a reference voltage module configured to select a first reference voltage between a first threshold voltage corresponding to a first state of a memory cell and a second threshold voltage corresponding to a second state of the memory cell, wherein the first state and the second state are consecutive states of the memory cell, and wherein the first threshold voltage is less than the second threshold voltage, and select a second reference voltage, wherein the second reference voltage is less than the first reference voltage and greater than the first threshold voltage, and select a third reference voltage, wherein the third reference voltage is greater than the first reference voltage and less than the second threshold voltage; and a read module configured to perform a first read operation to determine a state of the memory cell based on the first reference voltage, and in response to a first failure to decode data read from the memory cell in the first read operation, perform a second read operation to determine the state of the memory cell based on the second reference voltage, and perform a third read operation to determine the state of the memory cell based on the third reference voltage.