Memory module for detecting and correcting a row direction error and a column direction error
A memory module includes a plurality of first memory chips and a second memory chip. Raw data is stored in the plurality of first memory chips. Parity data generated based on the raw data is stored in the second memory chip. Each of the first memory chips and the second memory chip is configured to exchange data with a controller based on a burst length unit. The second memory chip stores a first parity data generated from the raw data by a first error correction method, and stores a second parity data generated from the raw data and the first parity data by a second error correction method.
1. A memory module comprising:
a plurality of first memory chips configure to store raw data; and
a second memory chip configure to store parity data generated using the raw data,
a controller configured to exchange data with each of the first memory chips and the second memory chip in burst length units, and
wherein the second memory chip stores a first parity data generated from the raw data, and to store a second parity data generated from the raw data and the first parity data, and
wherein the first parity data and the second parity data are generated using different error correction codes.
2. The memory module of claim 1 , wherein the first parity data is generated using a Reed-Solomon (RS) code.
3. The memory module of claim 2 , wherein the second parity data is generated using a single error correction double error detection (SECDED) method.
4. The memory module according to claim 3 , wherein the number of the first memory chips is 4.
5. The memory module according to claim 4 , wherein each of the first memory chips and the second memory chip is configured to simultaneously output eight bits.
6. The memory module of claim 5 , wherein the first parity data includes parity bits generated using the Reed-Solomon (RS) code from four symbols, each symbol including 8 bits.
7. The memory module of claim 6 , wherein the second parity data includes second to eighth parity bits generated using the single error correction double error detection (SECDED) method applied to the four symbols and the parity bits.
8. The memory module of claim 7 , wherein each of the first memory chips and the second memory chip comprises:
a plurality of banks;
a peripheral circuit configured to receive a command and an address from the controller, transfer the command and the address to the plurality of banks, and exchange data between the controller and the plurality of banks, and
each of the plurality of banks comprises:
a memory cell array including a plurality of memory cells;
a row decoder connected to the plurality of memory cells through word lines;
bit line sense amplifiers connected to the plurality of memory cells through bit lines; and
a column decoder configured to connect some of the bit line sense amplifiers with the peripheral circuit.
9. The memory module of claim 8 , wherein the memory cell array includes a plurality of data blocks, and
each of the plurality of data blocks includes 128 bits.
10. The memory module of claim 9 , wherein each of the plurality of data blocks included in the second memory chip comprises:
a first parity data region in which the first parity data is stored; and
a second parity data region in which the second parity data is stored.
11. The memory module of claim 10 , wherein a ratio of the first parity data region to the second parity data region is 1:7.
12. The memory module of claim 11 , wherein the first parity data region is 16 bits and the second parity data region is 112 bits.