Erase-suspend system and method
View Patent ↗A method for suspending an erase operation performed on a group of memory cells in a flash memory circuit is disclosed. One example method includes providing to the memory circuit a command to erase the group of memory cells via a plurality of erase pulses. After applying an erase pulse, if it is determined that another operation has a priority higher than a predetermined threshold, the method suspends the erase operation, performs the other operation, and then resumes the erase operation.
1. A method for performing an erase operation in a flash memory device, the method comprising:
initiating an erase operation on a group of memory cells, the erase operation including a plurality of erase pulses;
after a predetermined number of erase pulses, determining if a subsequent operation is ready to be performed;
suspending the erase operation if the subsequent operation is ready to be performed;
performing the subsequent operation; and
resuming the erase operation.
2. The method of claim 1 , further comprising:
determining the subsequent operation has a higher priority than the erase operation.
3. The method of claim 1 , wherein the subsequent operation is performed on a different group of memory cells.
4. The method of claim 1 , further comprising:
setting the predetermined number of erase pulses to a maximum number of erase pulses to be performed by the erase operation before the erase operation is suspended.
5. The method of claim 4 , wherein the maximum number of erase pulses is one.
6. The method of claim 1 , further comprising:
receiving an indication that the erase operation is not completed,
wherein the erase operation is suspended upon receiving the indication that the erase operation is not completed.
7. The method of claim 1 , further comprising:
setting one or more parameters used to generate one or more of the plurality of erase pulses.
8. The method of claim 7 , wherein the one or more parameters includes a starting pulse voltage.
9. The method of claim 7 , wherein the one or more parameters includes an incremental adjustment in a pulse magnitude between subsequent pulses.
10. The method of claim 7 , wherein the one or more parameters includes a pulse width.
11. The method of claim 1 , further comprising:
prior to resuming the erase operation, resetting one or more existing parameters used to generate one or more of the plurality of erase pulses based on one or more saved parameters.
12. A machine-readable storage media having instructions stored thereon that, when executed by a processor, perform a method for suspending an erase operation, the method comprising:
providing to a flash memory circuit a first instruction to erase a group of memory cells using the erase operation;
receiving a first indication that the erase operation is not completed if the group of memory cells has not been fully erased after a predetermined number of erase pulses has been performed;
receiving a second indication that a subsequent operation has a priority above a predetermined threshold;
suspending the erase operation in response to receiving the first indication and the second indication;
performing the subsequent operation; and
resuming the erase operation.
13. The machine-readable storage media of claim 12 , wherein the predetermined threshold is the priority of the erase operation.
14. The machine-readable storage media of claim 12 , the method further comprising providing to the flash memory circuit one or more parameters to use in generating one or more of the erase pulses to be used in the erase operation.
15. The machine-readable storage media of claim 12 , the method further comprising:
after suspending and prior to resuming the erase operation, providing to the flash memory circuit one or more parameters to use in generating one or more subsequent erase pulses initiated after resuming the erase operation.
16. The machine-readable storage media of claim 15 , wherein the one or more parameters includes one or more of a starting pulse voltage, an amplitude increment, and a pulse width.
17. The machine-readable storage media of claim 15 , wherein the erase operation is an incremental stepping pulse erase operation.
18. The machine-readable storage media of claim 12 , wherein the resuming the erase operation comprises:
providing to the flash memory circuit a second instruction to continue erasing the group of memory cells.
19. A system, comprising:
a flash memory circuit, the flash memory circuit including one or more blocks of memory; and
a controller operably connected to the flash memory circuit, the controller operable to:
provide to the flash memory circuit an instruction to erase the block of memory cells using an erase operation;
receive a first indication that the erase operation is not completed if the block of memory cells has not been fully erased after a predetermined number of erase pulses;
receive a second indication that a subsequent operation is ready to be performed; and
on receiving the first indication and the second indication, suspend the erase operation, perform the subsequent operation, and resume the erase operation.
20. The system of claim 19 , wherein the controller is further operable to:
determine the subsequent operation is associated with a priority level above a predetermined threshold.