Memory system
According to one embodiment, a memory system includes a memory chip and a controller coupled to the memory chip and configured to: instruct the memory chip to execute a write operation in one of a first operation mode and a second operation mode, a program voltage used in the second operation mode being determined on the basis of first information obtained in the first operation mode; manage a power consumption value of the second operation mode on the basis of the first information; and perform power throttling control on the basis of the managed power consumption value.
1. A memory system comprising:
a nonvolatile memory including a plurality of regions; and
a controller coupled to the nonvolatile memo and configured to:
instruct the nonvolatile memory to execute a write operation in one of a first operation mode and a second operation mode, a program voltage used in the second operation mode being determined on the basis of first information obtained in the first operation mode, wherein
the nonvolatile memory is configured to transmit the first information to the controller after executing the write operation in the first operation mode, and
the controller is further configured to:
manage, for each of the plurality of regions;
a status indicating whether the first information is available or not, and
a first power consumption value of the first operation mode and a second power consumption value of the second operation mode;
in instructing the write operation to the nonvolatile memory;
determine, if the first information is not available, a power consumption value of the write operation as the first power consumption value, and
determine, if the first information is available, the power consumption value of the write operation as the second power consumption value;
perform power throttling control on the basis of the determined power consumption value of the write operation;
update the second power consumption value of the second operation mode on the basis of the first information; and
upon a data erase operation being performed on one region of the plurality of regions, change the status of the one region to indicate that the first information is not available.
2. The memory system according to claim 1 , wherein
the write operation includes a plurality of program loops each of the program loops includes a program operation and a program verify operation, and
the program voltage used in an initial program loop of the second operation mode is higher than a program voltage used in an initial program loop of the first operation mode.
3. The memory system according to claim 2 , wherein
the first information includes the number of the program loops when the write operation is executed in the first operation mode.
4. The memory system according to claim 2 , wherein
the program voltage used in the initial program loop of the second operation mode is determined on the basis of the first information.
5. The memory system according to claim 2 , wherein
the number of the program loops of the second operation mode is smaller than the number of the program loops of the first operation mode.
6. The memory system according to claim 2 , wherein
the program voltage in the first operation mode is stepped up each time the program loop is repeated.
7. The memory system according to claim 2 , wherein
the program voltage in the second operation mode is stepped up each time the program loop is repeated.
8. The memory system according to claim 2 , wherein
the program voltage used in the initial program loop of the second operation mode is lower than a program voltage used in a last program loop of the first operation mode.
9. The memory system according to claim 1 , wherein
the first information includes writing speed information of the write operation in the first operation mode.
10. The memory system according to claim 1 , wherein
each of the plurality of regions is a block, and
the controller is configured to determine the power consumption value of the write operation in a unit of the block.
11. The memory system according to claim 1 , wherein
each of the plurality of regions is a memory chip, and
the controller is configured to determine the power consumption value of the write operation in a unit of the memory chip.
12. The memory system according to claim 1 , wherein
the nonvolatile memory is a NAND-type flash memory.
13. The memory system according to claim 1 , wherein
power consumed in the first operation mode is more than power consumed in the second operation mode.
14. The memory system according to claim 1 , wherein
a power consumption value of the first operation mode is larger than a power consumption value of the second operation mode.
15. The memory system according to claim 14 , wherein
the number of write operations simultaneously executable in the second operation mode is larger the number of write operations simultaneously executable in the first operation mode.
16. The memory system according to claim 1 , wherein
when a requested operation that is to be a target of the power throttling control is finished in the nonvolatile memory, the controller modifies a power consumable amount for the power throttling control.
17. The memory system according to claim 16 , wherein
the controller is further configured to determine whether or not a command is executable, on the basis of a result of comparing a power consumption value of the command and the power consumable amount.
18. The memory system according to claim 1 , wherein
the write operation and an erase operation are included in a target of the power throttling control.