METHOD FOR CHANGING READ PARAMETER FOR IMPROVING READ PERFORMANCE AND APPARATUSES USING THE SAME

摘要

PURPOSE: An apparatus and method for changing a read parameter are provided to reduce an ECC decoding failure by previously changing a lead parameter after a read operation or an ECC decoding of read data is successful. CONSTITUTION: A first data saved in a memory cell array(22) is read by using a read voltage. The read voltage is changed to read a second data saved in a first region of the memory cell array according to a comparison result of a count value of 0 and 1 included in the first data and a reference count value. The changed read voltage information is saved in a second region of the memory cell array. A second data is read by using the changed read voltage corresponding to the information saved in a second region.