Double program debug method for NAND memory using self-verification by internal firmware

A NAND flash memory device comprising:

• a memory array comprising a plurality of pages, each page of the plurality of pages comprising a plurality of memory cells corresponding to a word line;
• and
• a peripheral circuit coupled to the plurality of pages via the word line and configured to program a selected page of the NAND flash memory device according to first and second programming data using:
• a plurality of programming operations using a plurality of programming voltages;
• a plurality of verifying operations, wherein ones of the plurality of verifying operations are performed after corresponding ones of the plurality of programming operations to determine whether programmed memory cells of the selected page have threshold voltage levels according to the first or second programming data;
• and
• a self-verification operation on the selected page to determine whether data stored at the selected page was overwritten,
• wherein the NAND flash memory device is configured to generate a fail indication upon determining that the data stored at the selected page was overwritten.

A system comprising:

• one or more computing devices;
• and
• a NAND flash memory device comprising:
• a memory array comprising a plurality of pages, each page of the plurality of pages comprising a plurality of memory cells corresponding to a word line;
• and
• a peripheral circuit coupled to the plurality of pages via the word line and configured to:
• program a selected page of the NAND flash memory device according to first and second programming data, wherein the programming of the selected page comprises:
• a plurality of programming operations using a plurality of programming voltages;
• and
• a plurality of verifying operations, wherein ones of the plurality of verifying operations are performed after corresponding ones of the plurality of programming operations to determine whether programmed memory cells of the selected page have threshold voltage levels according to the first or second programming data;
• and
• perform a self-verification on the selected page to determine whether data stored at the selected page was overwritten;
• and
• wherein the NAND flash memory device is configured to generate a fail indication upon determining that data stored at the selected page was overwritten.