Method and apparatus for writing nonvolatile memory using multiple-page programming
A method of storing information or data in a nonvolatile memory device with multiple-page programming. The method, in one aspect, is able to activate a first drain select gate (“DSG”) signal. After loading the first data from a bit line (“BL”) to a nonvolatile memory page of a first memory block in response to activation of the first DSG signal during a first clock cycle, the first DSG signal is deactivated. Upon activating a second DSG signal, the second data is loaded from the BL to a nonvolatile memory page of a second memory block. The first data and the second data are simultaneously written to the first memory block and the second memory block, respectively.
1. A method of storing information in a nonvolatile memory device, comprising:
presetting a plurality of cell strings associated with a plurality of memory blocks of the memory device to an inhibit condition by setting a bit line associated with the cell strings to an inhibit voltage level and then pulsing a plurality of drain select gates associated with the plurality of cell strings to pass the inhibit voltage level to the cell strings;
ramping up a selected word line for each of the plurality of memory blocks to a program voltage level;
ramping up unselected word lines of the plurality of memory blocks to a pass voltage level; and
repeating multiple programming operations while maintaining the word line voltage levels from a first programming operation to a last programming operation, wherein the multiple programming operations program two or more memory blocks, and wherein each programming operation comprises:
applying data to a selected bit line; and
pulsing a drain select gate (DSG) associated with a selected memory block to load the data on the selected bit line into the selected memory block.
2. The method of claim 1 , further comprising:
applying additional data to the bit lines; and
pulsing a DSG associated with a next selected memory block to load the additional data on the bit lines into the next selected memory block.
3. The method of claim 1 , further comprising repeating the operations of applying and pulsing for each of one or more additional memory blocks until the plurality of memory blocks have been loaded.
4. The method of claim 3 , wherein when the operation of repeating is completed the plurality of memory blocks are programmed substantially simultaneously.
5. The method of claim 1 , wherein the operation of presetting comprises:
applying VDD to all bit lines of the plurality of memory blocks; and
applying VDD to all drain select gates of the plurality of memory blocks.
6. The method of claim 1 , wherein the ramping up of the selected word line and the ramping up of the unselected word lines is performed substantially together.
7. The method of claim 1 , wherein the pulsing comprises:
increasing a voltage level on the drain select gate to Vdd; and
reducing the voltage level on the drain select gate to Vss after a selected time interval has expired.
8. The method of claim 1 , wherein each memory block comprises a cell string having a plurality of NAND nonvolatile memory cells.
9. A nonvolatile memory device, comprising:
an array of flash memory cells organized in multiple memory blocks, wherein each of the multiple memory blocks is further arranged in a plurality of pages having cell strings; and
multiple block decoders coupled to the multiple memory blocks, and wherein the multiple block decoders perform operations of:
presetting a plurality of cell strings associated with a plurality of memory blocks of the memory device to an inhibit condition by setting a bit line associated with the cell strings to an inhibit voltage level and then pulsing a plurality of drain select gates associated with the plurality of cell strings to pass the inhibit voltage level to the cell strings;
ramping up a selected word line of the plurality of memory blocks to a program voltage level;
ramping up unselected word lines of the plurality of memory blocks to a pass voltage level;
applying selected data to a selected bit line;
pulsing a drain select gate (DSG) associated with a selected memory block to load the data on the selected bit line into the selected memory block; and
repeating the operation of pulsing to program multiple memory blocks while maintaining the word line voltage levels from a first programming operation to a last programming operation.
10. The apparatus of claim 9 , wherein the multiple block decoders perform operations of:
applying additional data to the bit lines; and
pulsing a DSG associated with a next selected memory block to load the additional data on the bit lines into a next selected memory block.
11. The apparatus of claim 9 , wherein the multiple block decoders repeat the operations of applying and pulsing for each of one or more additional memory blocks until the plurality of memory blocks have been loaded.
12. The apparatus of claim 11 , wherein when the multiple block decoders complete the operation of repeating, the plurality of memory blocks are programmed substantially simultaneously.
13. The apparatus of claim 9 , wherein the multiple block decoders perform the operation of presetting by:
applying VDD to all bit lines of the plurality of memory blocks; and
applying VDD to all drain select gates of the plurality of memory blocks.
14. The apparatus of claim 9 , wherein multiple block decoders perform the ramping up of the selected word line and the ramping up of the unselected word lines substantially together.
15. The apparatus of claim 9 , wherein the pulsing comprises:
increasing a voltage level on the drain select gate to Vdd; and
reducing the voltage level on the drain select gate to Vss after a selected time interval has expired.
16. The apparatus of claim 9 , wherein each memory block comprises a cell string having a plurality of NAND nonvolatile memory cells.
17. A method for programming a nonvolatile memory device, the method comprising:
setting selected word lines of a plurality of memory blocks to a program voltage level and remaining word lines to a pass voltage level;
pulsing a drain select gate (DSG) associated with a first memory block to program bit line data into the first memory block;
pulsing a drain select gate (DSG) associated with a second memory block to program the bit line data into the second memory block; and
maintaining the voltage levels of word lines associated with the first and second memory blocks beginning from the pulsing of the DSG associated with the first memory block to the pulsing of the DSG associated with the second memory block.