Flash memory apparatus and method for generating read voltage thereof

The flash memory apparatus comprises:

• a cell array in which a plurality of main cells and a plurality of CAM cell are arranged;
• a control unit configured to select main cells to which a program operation is to be performed among the plurality of main cells, when a program operation command is inputted, perform a program operation on the selected main cells, detect threshold voltage change data of the main cells to which the program operation has been performed, perform a leveling operation to divide the threshold voltage change data of the main block to have a plurality of levels, reads the plurality of levels with different value according to a level position based on verification lines previously set for determining whether the program operation is correctly performed, set a trimming value corresponding to the read plurality of levels, and store the set trimming value in the CAM cells;
• and
• a read voltage generation unit configured to generate a read voltage according to the trimming value stored in the CAM cell.

A method for generating a read voltage of a flash memory apparatus including a plurality of main blocks, a CAM block, and a security block, the method comprising:

• selecting two or more main blocks among the plurality of main blocks and performing a program operation on the selected main blocks;
• detecting threshold voltage distributions of the two or more main blocks to which the program operation has been performed;
• performing a leveling operation to divide the threshold voltage distributions of one of the plurality of main blocks to have a plurality of levels;
• reading the plurality of levels with different value according to a level position based on verification lines previously set for determining whether the program operation is correctly performed;
• setting a trimming value based on the read plurality of levels;
• and
• generating a read voltage according to the set trimming value.

A method for generating a read voltage of a flash memory apparatus in which a plurality of main cells and a plurality of CAM cells are arranged, the method comprising:

• selection one or more main cells among the plurality of main cells when a program operation command is inputted, and performing a first program operation and a second program operation on the selected main cells;
• detecting a first threshold voltage distribution to which the first program operation has been performed and a second threshold voltage distribution to which the second program operation has been performed, when the first program operation and the second program operation are passed;
• dividing a gap between the first threshold voltage distribution and the second threshold voltage distribution to have a plurality of levels at constant intervals;
• reading the plurality of levels with different value according to a level position based on verification lines previously set for determining whether the program operation is correctly performed;
• setting the read levels as the trimming value;
• storing the set trimming value in the CAM cells;
• reading the trimming value stored in the CAM cells when a read command in inputted;
• and
• generating a read voltage according to the read trimming value.