Semiconductor memory device and memory system
A semiconductor memory device includes a memory cell, and a control circuit configured to execute a writing operation on the memory cell in response to a write command. The writing operation includes a first operation in which a first initial program voltage is applied and a second operation in which a second initial program voltage higher than the first initial program voltage is applied. The control circuit, in response to a status inquiry command, outputs a first signal when the status inquiry command is received during execution of the first operation, and outputs a second signal which is different from the first signal when the status inquiry command is received during execution of the second operation.
1. A semiconductor memory device comprising:
a memory cell; and
a control circuit configured to execute a writing operation on the memory cell in response to a write command, the writing operation including a first operation in which a first initial program voltage is applied and a second operation in which a second initial program voltage higher than the first initial program voltage is applied,
wherein the control circuit, in response to a status inquiry command, outputs a first signal when the status inquiry command is received during execution of the first operation, and outputs a second signal which is different from the first signal when the status inquiry command is received during execution of the second operation.
2. The device according to claim 1 , wherein
data which are written into the memory cell include first data and second data which are separately received and stored in different latches, and
the first data and the second data are stored in the latches until the first operation is completed.
3. The device according to claim 2 , wherein
the first data and the second data become invalid in the latches during the second operation.
4. The device according to claim 3 , wherein the control circuit, in response to a suspend command, suspends the writing operation, and thereafter, in response to a restart write command, executes the first and second operations without storing the first data and the second data in the latches if the first signal was output in response to the status inquiry command, and only the second operation after storing the first data and the second data in the latches if the second signal was output in response to the status inquiry command.
5. The device according to claim 1 , wherein upon completion of the first operation, the control circuit stores a first value into a status register indicating that the first operation has completed and upon completion of the second operation, stores a second value which is different from the first value in the status register.
6. The device according to claim 5 , wherein the first signal is output in response to the status inquiry command if the status register stores the first value and the second signal is output in response to the status inquiry command if the status register stores the second value.
7. A semiconductor memory device comprising:
a memory cell; and
a control circuit configured to execute a writing operation on the memory cell in response to a write command, the writing operation including a first operation in which a first initial program voltage is applied and a second operation in which a second initial program voltage higher than the first initial program voltage is applied,
wherein the control circuit, in response to a first command, suspends the writing operation, and thereafter, in response to a second command outputs a first signal when the first command is received during execution of the first operation, and outputs a second signal which is different from the first signal when the first command is received during execution of the first operation.
8. The device according to claim 7 , wherein
the control circuit, in response to a first command, suspends the writing operation after completion of the first operation if the first command is received during the first operation.
9. The device according to claim 8 , wherein
data which are written into the memory cell include first data and second data which are separately received and stored in different latches, and
the first data and the second data are stored in the latches until the first operation is completed.
10. The device according to claim 9 , wherein
the first data and the second data become invalid in the latches during the second operation.
11. The device according to claim 10 , wherein the control circuit, in response to a restart write command, executes only the second operation after storing the first data and the second data in the latches.
12. The device according to claim 10 , wherein the control circuit executes an interrupting operation in response to a third command, and then performs a read of the first data written into the memory cell prior to restarting the suspended writing operation.
13. The device according to claim 7 , wherein upon completion of the first operation, the control circuit stores a first value into a status register indicating that the first operation has completed and upon start of the first operation, stores a second value which is different from the first value in the status register.
14. The device according to claim 13 , wherein the first signal is output in response to the second command if the status register stores the first value and the second signal is output in response to the second command if the status register stores the second value.
15. A memory system comprising:
a semiconductor memory device that includes a memory cell, and a control circuit configured to control operations on the memory cell; and
a memory controller configured to issue commands to the semiconductor memory device in response to instructions received from a host device,
wherein the memory controller transmits a first command which instructs the memory cell to perform a writing operation including a first operation and a second operation to the semiconductor memory device, and transmits a second command to the semiconductor memory device based on an instruction from the host device, and
wherein the control circuit performs the first operation using a first initial voltage, and the second operation using a second initial voltage which is higher than the first initial voltage, and in response to the second command, transmits a first signal to the memory controller when the second command is received during execution of the first operation, and transmits a second signal which is different from the first signal to the memory controller when the second command is received during execution of the second operation.
16. The system according to claim 15 , wherein
the memory controller issues an interrupting command to the control circuit after receiving the first or second signal from the control circuit.
17. The system according to claim 16 , wherein the memory controller transmits a restart write command when a ready signal is received from the control circuit after the memory controller issued the interrupting command to the control circuit.
18. The system according to claim 17 , wherein the restart write command is one of a first type that does not cause reloading of write data into latches that the control circuit uses during the writing operation, and a second type that causes reloading of the write data into the latches.
19. The system according to claim 18 , wherein the restart write command is the first type if the first signal was received from the control circuit in response to the second command.
20. The system according to claim 18 , wherein the restart write command is the second type if the second signal was received from the control circuit in response to the second command.