Patent ID: 8238162

Claim:
A method for detecting a disturbed condition of a selected memory cell in a memory device having a reference cell, the method comprising: applying a first set of conditions to the selected memory cell and the reference cell, the first set of conditions being suitable for detecting whether the selected memory cell is programmed; applying a second set of conditions to the selected memory cell and the reference cell, the second set of conditions being suitable for detecting whether the selected memory cell is programmed, and the second set of conditions being different from the first set of conditions; and identifying the selected memory cell as having the disturbed condition if the selected memory cell responds as having been programmed in response to only one of the first and second sets of conditions, wherein the first set of conditions includes a word line voltage applied to the gate of the selected memory cell, and a first reference word line voltage applied to the gate of the reference cell, and wherein the second set of conditions includes the word line voltage applied to the gate of the selected memory cell, and a second reference word line voltage applied to the gate of the reference cell, wherein the second reference word line voltage is less than the first reference word line voltage.