Non-volatile semiconductor memory device
View Patent ↗When a non-volatile memory write error occurs in a card storage device containing a non-volatile memory and an error correction circuit, write data is read from the non-volatile memory and a check is made if the error can be corrected by the error correction circuit. If the error can be corrected, the write operation is ended. If the error correction circuit cannot correct the error, substitute processing is performed to write data into some other area.
1. A non-volatile memory comprising:
a plurality of nonvolatile memory cells; and an error correcting circuit,
wherein a program command accompanied with address information and first data are received from outside,
wherein, in a program operation executed in response to said program command, first nonvolatile memory cells of said plurality of nonvolatile memory cells are selected in accordance with said address information and programmed with said first data,
wherein, after said first nonvolatile memory cells are programmed with said first data in said program operation, second nonvolatile memory cells of said plurality of nonvolatile memory cells are selected and second data stored therein are read out,
wherein said error correcting circuit judges whether said second data includes one or more errors and corrects said second data to create third data when said second data includes one or more errors, and
wherein said second nonvolatile memory cells are programmed with said third data after said second data is corrected by said error correcting circuit.
2. A nonvolatile memory according to claim 1 , wherein, after said first data is programmed and before said second nonvolatile memory cells are selected:
said first nonvolatile memory cells are selected and fourth data stored therein is read out,
said error correcting circuit judges whether said fourth data includes errors which are correctable or not correctable,
said first nonvolatile memory cells are programmed again with said first data, if said fourth data includes errors which are not correctable by said error correcting circuit, and
programming of said first nonvolatile memory cells with said first data is completed if said fourth data includes errors which are correctable by said error correcting circuit.
3. A nonvolatile memory according to claim 2 , wherein after said first data is programmed:
said error correcting circuit judges whether said fourth data includes errors which are correctable or not correctable, and
when said error correcting judges that said fourth data includes errors which are not correctable, third nonvolatile memory cells of said plurality of nonvolatile memory cells, different from said first nonvolatile memory cells, are selected and programmed with said first data.
4. A nonvolatile memory according to claim 3 , further comprising a controller including said error correcting circuit.
5. A nonvolatile memory according to claim 4 , wherein:
said controller further includes a buffer memory, and
said first data is stored in said buffer memory until completion of programming with said first data.
6. A nonvolatile memory according to claim 1 , wherein each of said plurality of nonvolatile memory cells is a one-bit memory cell.
7. A nonvolatile memory according to claim 1 , wherein each of said plurality of nonvolatile memory cells is a multiple-bit memory cell.