Flexible memory operations in NAND flash devices
View Patent ↗A flash memory device having at least two bank, where the each bank has an independently configurable page size and core controller. The core controller is local to each bank, and governs memory access operations for the bank that include read, program and erase operations. Each core controller controls timing and activation of row circuits, column circuits, voltage generators, and local input/output path circuits for a corresponding memory access operation of the bank. Concurrent operations are executable in multiple banks to improve performance. Each bank has a page size that is configurable with page size configuration data such that only selected wordlines are activated in response to address data. The configuration data can be loaded into the memory device upon power up for a static page configuration of the bank, or the configuration data can be received with each command to allow for dynamic page configuration of the bank.
1. A flash memory device comprising:
a memory element configured to perform memory operations, the memory element including at least two memory banks each having local core circuitry, each of the at least two memory banks having a configurable page size for receiving and providing data having different page sizes during memory operations; and
core controller circuitry including at least two core controllers configured to receive control signals corresponding to the memory operations, the at least two core controllers operating the local core circuitry of the at least two memory banks concurrently in response to the received control signals.
2. The flash memory device of claim 1 , further including a row predecoder receiving a row address and a bank address, the row predecoder providing predecoded row addresses corresponding to a selected memory bank of the at least two memory banks in response to the bank address and the row address.
3. The flash memory device of claim 1 , further including a column predecoder receiving a column address and a bank address, the column predecoder providing a predecoded column address corresponding to a selected memory bank of the at least two memory banks in response to the bank address and the row address.
4. The flash memory device of claim 1 , further including a selector for selectively passing the control signals to a selected core controller of the at least two core controllers in response to a bank address, the selected core controller providing bank control signals in response to the control signals.
5. The flash memory device of claim 4 , further including a command interpreter for receiving a command, and for decoding the command to provide the control signals and the bank address.
6. The flash memory device of claim 1 , wherein each of the at least two memory banks includes two memory planes each having NAND memory cell strings connected to bitlines and wordlines connected to flash memory cells of each of the NAND memory cell strings.
7. The flash memory device of claim 6 , wherein the two memory planes are each adjacent a shared row decoder.
8. The flash memory device of claim 6 , wherein the flash memory cells connected to a wordline forms a page unit having a predetermined page size.
9. The flash memory device of claim 8 , wherein the configurable page size includes one of a single page unit from one of the two memory planes and two page units.
10. The flash memory device of claim 8 , further including page size configurators corresponding to each of the each of the at least two memory banks for selectively enabling activation of at least one wordline in each of the two memory planes in response to an address.
11. The flash memory device of claim 10 , wherein each of the at least two memory banks includes one of the page size configurators.
12. The flash memory device of claim 10 , wherein each of the two memory planes includes a row decoder enabled by the page size configurator for driving the at least one wordline with a global row drive signal.
13. The flash memory device of claim 10 , wherein the two memory planes are each adjacent a shared row decoder enabled by the page size configurator for driving the at least one wordline with a global row drive signal.
14. The flash memory device of claim 13 , wherein the shared row decoder includes a row driver for selectively passing the global row drive signal to the at least one wordline in response to first and second enable signals provided by the page size configurator.
15. The flash memory device of claim 14 , wherein the row driver includes a first pass transistor for passing the global row drive signal to a first wordline in response to the first enable signal, and a second pass transistor for passing the global row drive signal to a second wordline in response to the second enable signal.
16. The flash memory device of claim 15 , wherein the first enable signal and the second enable signal are driven to a high voltage level greater than a voltage level of the global row drive signal.
17. The flash memory device of claim 16 , wherein the shared row decoder further includes a block decoder for providing a master voltage as the first enable signal in response to a first plane select signal, and as the second enable signal in response to a second plane select signal.
18. The flash memory device of claim 1 , wherein each of the at least two memory banks includes four memory planes each having NAND memory cell strings connected to bitlines and wordlines connected to flash memory cells of each of the NAND memory cell strings.
19. The flash memory device of claim 18 , further including a page size configurator corresponding to one of the at least two memory banks for selectively enabling activation of at least one wordline in each of the four memory planes of the one of the at least two memory banks, in response to an address.
20. The flash memory device of claim 19 , wherein the four memory planes of the one of the at least two memory banks are arranged as a first tile and a second tile, the first tile and the second tile each having memory planes adjacent a shared row decoder.
21. The flash memory device of claim 20 , wherein the page size configurator selectively enables activation of at least one wordline in each of the four memory planes in response to a tile address and a plane address.
22. The flash memory device of claim 21 , wherein the flash memory cells connected to one wordline forms a page unit having a predetermined page size, and the configurable page size includes any combination of page units from each of the four memory planes.
23. A method for operating a flash memory device including at least first and second memory banks, each having a configurable page size, comprising:
providing page size configuration commands after power up of the flash memory device, the page size configuration commands including configuration data stored in configuration resisters corresponding to the first and second memory banks;
executing a first memory operation in the first memory bank; and
executing a second memory operation in the second memory bank while the first memory operation is being executed in the first memory bank.
24. The method of claim 23 , wherein the page sizes of the first and second memory banks are configured after the power up of the flash memory device.
25. The method of claim 24 , wherein the page size configuration commands are provided any time before and after the first memory operation and the second memory operation are executed.
26. The method of claim 23 , wherein executing the first memory operation includes configuring the page size of the first memory bank and executing the second memory operation includes configuring the page size of the second memory bank.
27. The method of claim 26 , wherein executing the first memory operation includes receiving a first command including an op code corresponding to the first memory operation and configuration data corresponding to the first memory bank page size.
28. The method of claim 26 , wherein executing the second memory operation includes receiving a first command including an op code corresponding to the second memory operation and configuration data corresponding to the second memory bank page size.
29. The method of claim 23 , wherein the first memory operation and the second memory operation includes one of a read operation, a program operation and an erase operation.
30. A system comprising:
a memory controller providing commands for executing corresponding memory operations; and
a memory system having at least one memory device, the at least one memory device having at least two memory banks, each of the at least two memory banks having a configurable page size and controllable for executing memory operations corresponding to the commands concurrently, the at least one memory device further having core controller circuitry for receiving control signals corresponding to the commands, the core controller being configured to concurrently control local core circuits corresponding to each of the at least two memory banks in response to the received control signals.
31. The system of claim 30 wherein the memory system having at least one memory device includes
a first memory device connected to a common bus, the common bus being connected to the memory controller, and
a second memory device connected to the common bus and in parallel with the first memory device.
32. The system of claim 30 wherein the memory system having at least one memory device includes
a first memory device connected in series to the memory controller and having inputs for receiving the commands and outputs for providing the commands, and
a second memory device connected in series to the first memory device and having inputs for receiving the commands.
33. The system of claim 32 wherein the second memory device has outputs for providing the commands to the memory controller.
34. The system of claim 30 , wherein the at least one memory device further includes a command interpreter for decoding the commands and providing the control signals.