Scan sensing method that improves sensing margins
Systems and methods for improving memory cell sensing margins by utilizing an optimal reference stimulus. A stimulus component applies a plurality of different reference stimuli to a plurality of memory cells of a memory device. A sense component senses a characteristic of each memory cell of the plurality of memory cells as a function of the serially applied plurality of different reference stimuli. An analysis component computes an optimal reference stimulus by selecting one of the plurality of different reference stimuli, the one of the plurality of different reference stimuli associated with an absolute minima of number of memory cell characteristics that changed state as a function of the applied plurality of different reference stimuli.
1. A system comprising:
a stimulus component that applies a plurality of different reference stimuli to a plurality of memory cells of a memory device;
a sense component that senses a characteristic of each memory cell of the plurality of memory cells as a function of the applied plurality of different reference stimuli; and
an analysis component that computes an optimal reference stimulus by selecting one of the plurality of different reference stimuli, the one of the plurality of different reference stimuli associated with an absolute minima of number of memory cell characteristics that changed state as a function of the applied plurality of different reference stimuli.
2. The system of claim 1 , wherein the stimulus component applies the optimal reference stimulus to each memory cell of the plurality of memory cells and wherein the sense component senses the characteristic of each memory cell of the plurality of memory cells as a function of the applied optimal reference stimulus.
3. The system of claim 1 , further comprising a data store component that stores the sensed characteristic of each memory cell of the plurality of memory cells, wherein the analysis component computes the optimal reference stimulus as a function of the stored sensed characteristics.
4. The system of claim 3 , further comprising an artificial intelligence component that automatically applies the plurality of different reference stimuli to the plurality of memory cells, senses the characteristic of each memory cell of the plurality of memory cells, stores the sensed characteristic of each memory cell of the plurality of memory cells, computes the optimal reference stimulus, and applies the optimal reference stimulus to each memory cell of the plurality of memory cells.
5. The system of claim 1 , wherein the plurality of different reference stimuli comprises at least one of voltage or current, and wherein the sensed characteristic of each memory cell comprises at least one of drain current, threshold voltage, logic state, or an output of one or more sense amplifiers, the one or more sense amplifiers coupled to at least one memory cell of the plurality of memory cells.
6. The system of claim 3 , wherein the stimulus component serially applies n different reference stimuli to the plurality of memory cells, wherein the sense component senses the characteristic of each memory cell of the plurality of memory cells as a function of the serially applied n different reference stimuli, and wherein the data store component stores the sensed characteristic of each memory cell of the plurality of memory cells.
7. The system of claim 6 , wherein the analysis component computes a number of stored sensed characteristics that changed state as a function of the serially applied n different reference stimuli, wherein the analysis component computes the optimal reference stimulus by selecting one of the serially applied n different reference stimuli, and wherein the one of the serially applied n different reference stimuli is associated with an absolute minima of number of memory cell characteristics that changed state as a function of the serially applied n different reference stimuli.
8. The system of claim 1 , wherein the sense component comprises one or more sense amplifiers.
9. The system of claim 8 , wherein the one or more sense amplifiers comprises one or more window comparators.
10. The system of claim 9 , wherein the sense component comprises one or more outputs of the one or more window comparators, the one or more window comparators coupled to at least one memory cell of the plurality of memory cells, and wherein the analysis component computes the optimal reference stimulus by selecting a reference stimulus within a window region of one of the one or more window comparators, the least number of memory cells of the plurality of memory cells activating the one or more outputs of the one of the one or more window comparators.
11. The system of claim 1 , wherein each memory cell of the plurality of memory cells is a volatile or non-volatile memory cell.
12. The system of claim 11 , wherein each memory cell of the plurality of memory cells is at least one of flash memory, multi-bit flash memory, read only memory (“ROM”), programmable ROM (“PROM”), erasable programmable read only memory (“EPROM”), electronically erasable programmable read only memory (“EEPROM”), random access memory (“RAM”), synchronous RAM (“SRAM”), dynamic RAM (“DRAM”), synchronous DRAM (“SDRAM”), double data rate SDRAM (“DDR SDRAM”), enhanced SDRAM (“ESDRAM”), Synchlink DRAM (“SLDRAM”), Rambus direct RAM (“RDRAM”), direct Rambus dynamic RAM (“DRDRAM”), Rambus dynamic RAM (“RDRAM”), or a combination thereof.
13. A method comprising:
applying a plurality of different reference stimuli to a plurality of memory cells of a memory device;
sensing a characteristic of each memory cell of the plurality of memory cells as a function of the applied plurality of different reference stimuli; and
computing an optimal reference stimulus by selecting one of the plurality of different reference stimuli, the one of the plurality of different reference stimuli associated with an absolute minima of number of memory cell characteristics that changed state as a function of the applied plurality of different reference stimuli.
14. The method of claim 13 , further comprising:
applying the optimal reference stimulus to each memory cell of the plurality of memory cells;
sensing the characteristic of each memory cell of the plurality of memory cells as a function of the applied optimal reference stimulus;
storing the sensed characteristic of each memory cell of the plurality of memory cells; and
computing the optimal reference stimulus as a function of the stored sensed characteristics.
15. The method of claim 14 , further comprising:
serially applying n different reference stimuli;
sensing the characteristic of each memory cell as a function of the serially applied n different reference stimuli; and
storing the sensed characteristic of each memory cell as a function of the serially applied n different reference stimuli.
16. The method of claim 15 , further comprising:
computing a number of stored sensed characteristics that changed state as a function of the serially applied n different reference stimuli; and
selecting one of the serially applied n different reference stimuli, the one of the serially applied n different reference stimuli associated with an absolute minima of number of memory cell characteristics that changed state as a function of the serially applied n different reference stimuli.
17. The method of claim 13 , further comprising:
sensing the characteristic of each memory cell of the plurality of memory cells as a function of one or more outputs of one or more window comparators, the one or more window comparators coupled to the plurality of memory cells; and
computing the optimal reference stimulus by selecting a reference stimulus within a window region of one of the one or more window comparators, the least number of memory cells activating the one or more outputs of the one of the one or more window comparators.
18. A system comprising:
a means for applying a plurality of different reference stimuli to a plurality of memory cells of a memory device;
a means for sensing a characteristic of each memory cell of the plurality of memory cells as a function of the applied plurality of different reference stimuli; and
a means for computing an optimal reference stimulus by selecting one of the plurality of different reference stimuli, the one of the plurality of different reference stimuli associated with an absolute minima of number of memory cell characteristics that changed state as a function of the applied plurality of different reference stimuli.
19. The system of claim 18 , further comprising:
a means for storing the sensed characteristic of each memory cell of the plurality of memory cells; and
a means for computing the optimal reference stimulus as a function of the stored sensed characteristics.
20. The system of claim 19 , further comprising:
a means for serially applying n different reference stimuli to the plurality of memory cells;
a means for sensing the characteristic of each memory cell as a function of the serially applied n different reference stimuli;
a means for computing the number of stored sensed characteristics that changed state as a function of the serially applied n different reference stimuli; and
a means for selecting one of the serially applied n different reference stimuli, the one of the serially applied n different reference stimuli associated with an absolute minima of number of memory cell characteristics that changed state as a function of the serially applied n different reference stimuli.