Electronic apparatus having data retention protection and operating method thereof

1. An electronic apparatus comprising:

a storage device having a plurality of memory blocks including a first memory block; and

a controller configured to control the storage device to perform a read operation for the first memory block in response to a read request of a host,

wherein the controller controls the storage device to perform a refresh operation for the first memory block based on whether there is a difference value between a current pass read voltage and a previous pass read voltage which were applied to the first memory block when performing the read operation, and whether there is a difference between a current erase/write count and a previous erase/write count for the first memory block.

2. The electronic apparatus according to claim 1 , wherein the controller comprises:

a processor configured to control general operations of the controller;

a memory including a block state table which stores state information for the previous pass read voltage and the previous erase/write count of the first memory block; and

a retention manager configured to calculate the difference value between the current pass read voltage and the previous pass read voltage,

compare the calculated difference value with a preset threshold value,

compare the current erase/write count with the previous erase/write count, and

provide the processor with a signal indicating a comparison result.

3. The electronic apparatus according to claim 2 , wherein the state information comprise the current erase/write count, the previous pass read voltage, and the previous erase/write count.

4. The electronic apparatus according to claim 2 , wherein the controller calculates the difference value by driving the retention manager through the processor when the read operation succeeds, compares the calculated difference value with the preset threshold value, and compares the current erase/write count with the previous erase/write count when the difference value is equal to or greater than the preset threshold value.

5. The electronic apparatus according to claim 4 , wherein the processor controls the storage device to perform the refresh operation for the first memory block when the current erase/write count and the previous erase/write count are equal.

6. The electronic apparatus according to claim 1 , wherein the controller further determines whether a read count for the first memory block is equal to or greater than a preset threshold count when the read operation fails, and further controls the storage device to perform the refresh operation for the first memory block when the read count is equal to or greater than the preset threshold count.

7. The electronic apparatus according to claim 6 , wherein, when the read count for the first memory block is less than the preset threshold count, the controller controls the storage device to change a read voltage and then controls the storage device to read out data again from the first memory block by applying the changed read voltage.

8. The electronic apparatus according to claim 1 , wherein the controller further controls the storage device to perform a retention state scan operation for each of the plurality of memory blocks except the first memory block when performing the refresh operation for the first memory block.

9. The electronic apparatus according to claim 8 , wherein the controller controls the storage device to perform the retention state scan operation while the electronic apparatus is in an idle state, is booted, or a garbage collection (GC) operation is performed in the storage device.

10. A memory system comprising:

a memory device including a memory block; and

a controller configured to:

store a previous pass read voltage, a current erase/write count, and a previous erase/write (EW) count of the memory block; and

control the memory device to perform a refresh operation to the memory block when a difference between the current pass read voltage and the previous pass read voltage is greater than a predetermined threshold and the current EW count and the previous EW count are equal.

11. An electronic apparatus having data retention protection comprising:

a data storage device including a plurality of memory blocks; and

a controller including a retention manager, and configured to control the data storage device to perform a read operation on a first memory block among the plurality of memory blocks in response to a read request from a host,

wherein the retention manager compares a pass read voltage applied to the first memory block in the current read operation with a stored previous pass read voltage applied to the first memory block during a last previous read operation to determine a voltage difference value when a current read operation is determined to be a success,

wherein the retention manager determines a current erase/write count for the first memory block and compares the current erase/write count with a stored previous erase/write count for the first memory block when the voltage difference value is greater than or equal to a preset voltage threshold value, and

wherein the retention manager performs a refresh operation for the first memory block when the current erase/write count is equal to the stored previous erase/write count.

12. The electronic apparatus of claim 11 ,

wherein the controller further includes a processor,

wherein the processor determines and stores a read count for the current read operation and compares the read count to a preset read count threshold when the current read operation is determined to be a failure, and

wherein the data storage device under control of the controller changes a read voltage applied to the first memory block in the current read operation and re-performs the current read operation based on the changed read voltage when the read count is less than the preset read count threshold.

13. The electronic apparatus of claim 12 ,

wherein the retention manager performs a refresh operation for the first memory block when the read count is greater than or equal to the preset read count threshold.

14. The electronic apparatus of claim 12 , wherein the controller further includes:

a block state table for storing the current erase/write count, the stored previous pass read voltage, and the stored previous erase/write count,

wherein the retention manager updates the stored previous pass read voltage when the current read operation is determined to be a success.

15. The electronic apparatus of claim 11 ,

wherein the controller further includes a processor, and

wherein the processor determines that the current read operation is a success when ECC (error correction code) decoding of data read by the current read operation is a pass.

16. The electronic apparatus of claim 15 , wherein the processor determines that the current read operation is a failure when ECC (error correction code) decoding of data read by the current read operation is a fail.

17. The electronic apparatus of claim 11 , wherein the retention manager performs a retention state scan operation for each of the plurality of memory blocks except the first memory block.

18. The electronic apparatus of claim 17 , wherein the retention state scan operation is performed as a background operation when the electronic apparatus is in an idle state, is booted, or a garbage collection is performed in the data storage device.