Patent ID: 7936601
Filing Date: 2011-05-03
Classification: G11C

Abstract:
1. A method of operating a multi-level non-volatile memory device comprising: accessing data, stored in the device, that is associated with read voltages; and modifying the read voltages applied to a plurality of multi-level non-volatile memory cells to discriminate between states stored by the cells in response to a read operation to the multi-level non-volatile memory device, wherein modifying comprises: applying a range of preliminary read voltages to a word line, associated with the cells, between an upper read voltage limit for a first state and a lower read voltage limit for a second state that is immediately adjacent to the first state; determining which of the preliminary read voltages activated a minimum number of the plurality of multi-level non-volatile memory cells to provide a read voltage to discriminate between the first and second states; and applying the read voltage to the word line to read the plurality of multi-level non-volatile memory cells to execute the read command.