Semiconductor memory device

1. A method of controlling a memory device comprising:

receiving a write instruction;

starting a write operation to a first address in response to the write instruction;

receiving a first read instruction of the first address;

suspending the write operation;

applying a read voltage to a word line corresponding to the first address in a first read operation in response to the first read instruction;

resuming the write operation after applying the read voltage;

receiving a second read instruction after applying the read voltage; and

outputting read data from a data register in response to the second read instruction during a period starting at resuming the write operation and ending at completion of the write operation.

2. The method according to claim 1 , further comprising:

setting a ready/busy signal to a busy state in response to the first read instruction; and

applying the read voltage during the busy state.

3. The method according to claim 1 , further comprising:

outputting the read data from the data register based on a read enable signal.

4. The method according to claim 1 , further comprising:

setting a ready/busy signal to a busy state in response to the write instruction; and

setting the ready/busy signal to a ready state when the data register is ready to be used.

5. The method according to claim 4 , wherein

setting the ready/busy signal to the ready state before receiving the first read instruction.

6. The method according to claim 1 , wherein

the write operation before suspending includes at least one loop of a program operation and a verify operation, and the write operation after resuming includes at least one loop of a program operation and a verify operation.

7. The method according to claim 1 , further comprising:

transmitting write data of a first memory cell held by a latch circuit in a sense amplifier to the data register as read data,

wherein the first memory cell is connected to the word line and writing of the write data to the first memory cell is not completed.

8. The method according to claim 1 , further comprising:

transmitting data read from a second memory cell to the data register as read data,

wherein the second memory cell is connected to the word line and writing of write data to the second memory cell is completed.

9. The method according to claim 1 , further comprising:

transmitting write data of a first memory cell held by a latch circuit to the data register as read data; and

transmitting data read from a second memory cell to the data register as read data;

wherein the first memory cell and the second memory cell are connected to the word line, writing of the write data to the first memory cell is not completed, and writing of the write data to the second memory cell is completed.

10. The method according to claim 1 , further comprising:

resuming the write operation after the first read operation.

11. The method according to claim 1 , further comprising:

setting a ready/busy signal to a busy state in response to the write instruction;

setting the ready/busy signal to a ready state from the busy state upon completion of transmission of write data from the data register to a latch circuit;

setting the ready/busy signal to the busy state from the ready state after the suspending the write operation; and

setting the ready/busy signal to the ready state from the busy state upon completion of the first read operation.

12. The method according to claim 1 , further comprising:

setting a ready/busy signal to a busy state in response to the write instruction;

setting the ready/busy signal to a ready state from the busy state after the suspending the write operation;

setting the ready/busy signal to the busy state from the ready state in response to the first read instruction;

setting the ready/busy signal to the ready state from the busy state upon completion of the first read operation; and

setting the ready/busy signal to the busy state from the ready state in response to a resume command to resume the write operation.

13. The method according to claim 1 , wherein the suspending the write operation is performed in response to a suspend command.

14. The method according to claim 1 , wherein the resuming the write operation is performed in response to a resume command.

15. The method according to claim 1 , wherein

the write operation includes repeating a program loop including a program operation and a verify operation,

the suspending the write operation is performed upon completion of the program operation in one program loop, and

the resuming the write operation is started by performing the verify operation in said one program loop.

16. The method according to claim 1 , wherein

the write operation includes repeating a program loop including a program operation and a verify operation,

the suspending the write operation is performed upon completion of the verify operation in one program loop, and

the resuming the write operation is started by performing the completed verify operation again in said one program loop.

17. The method according to claim 1 , wherein

the write operation includes repeating a program loop including a program operation and a verify operation,

the suspending the write operation is performed upon completion of the verify operation in one program loop, and

the resuming the write operation is started by performing the program operation in another program loop.

18. The method according to claim 1 , further comprising:

repeatedly performing a program loop including a program operation and a verify operation,

wherein a write voltage applied to the word line is stepped up every time the program operation is repeated.

19. The method according to claim 7 , wherein the transmitting the write data of the first memory cell held by the latch circuit in the sense amplifier to the data register as read data includes:

transmitting read data from the first memory cell to the data register; and

transmitting the write data from the latch circuit to the data register when the writing of the write data to the first memory cell is not completed.

20. The method according to claim 7 , wherein the transmitting the write data of the first memory cell held by the latch circuit in the sense amplifier to the data register as read data includes:

replacing data read from the first memory cell with the write data held by the latch circuit in the sense amplifier.