Dave's PCF WIP: Paragraphs

Paragraphs

Actions	Matter	Content	Para #	Notes	Modified
View Edit Delete	US10998041B1	One may observe that an increasing threshold voltage shift 720 of memory state D 730 is often accompanied by a decreasing threshold voltage shift 722 of memory state G 732. This relationship is another example of a correlation. Because the increasing threshold voltage shift 720 in memory state D 730 and the decreasing threshold voltage shift 722 in memory state G 732 occur in opposite directions, this correlation is referred to as a negative shift correlation 726. "Negative correlation" refers to a correlation in which two or more correlated things respond in an opposite manner to a particular influence, environment, action, or stimuli. For example, where threshold voltages of memory cells are represented by cell threshold voltage distributions and the cell threshold voltage distributions are mapped to memory states, memory cells within a first memory state are negatively correlated to memory cells within a second memory state when the correlated attribute changes in the opposite direction for the memory cells of the first memory state and the memory cells of the second memory state.	183	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	Said another way, if the correlated attribute increases for the memory cells of the first memory state and the correlated attribute decreases for the memory cells of the second memory state, this is a negative correlation. In certain embodiments, the correlated attribute may comprise a threshold voltage, or change in a cell threshold voltage distribution for a set of memory cells in memory states.	184	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	Positive shift correlation 724 and Negative shift correlation 726 are both examples of shift correlations. "Shift correlation" refers to a correlation in which memory cells of a cell threshold voltage distribution within a first memory state change or shift in threshold voltage (either increasing or decreasing) in response to passage of time, or use of a storage device, in a manner that correlates to a change or shift in threshold voltage (either increasing or decreasing) for memory cells of a cell threshold voltage distribution within a second memory state. A shift correlation may exist between any two memory states used for a set of memory cells.	185	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	In certain embodiments, the correlation may be represented by a magnitude and/or rate of change in an attribute or behavior between two or more things. The size of a value representing a correlation may directly relate to the strength or weakness of the correlation. Similarly, positive correlations may be represented by positive values for a correlation and negative correlations may be represented by negative values for a correlation. In one embodiment, a correlation is represented by a correlation factor. "Correlation factor" refers to a value that modifies a correlated attribute when the correlated attribute is multiplied by the correlation factor such that the correlated attribute accounts for a correlation associated with the correlation factor. For example, in one embodiment, the correlated attribute may be a read level. Each read level may mark a boundary between two adjacent memory states.	186	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	A correlation factor may represent how one memory state relates to another memory state such that multiplying the correlation factor by a current read level results in a correlated read level modified to account for the correlation. A correlation factor may be a real number and may be a positive number reflecting a positive correlation, a negative number reflecting a negative correlation, a zero representing no correlation, or a 1 representing a complete correlation. Correlation factors may be helpful in modifying a value to reflect a correlation. For example, in one embodiment, the value may be multiplied by a correlation factor such that the value then accounts for the correlation.	187	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	Correlations may be determined and quantified as correlation factors through a number of methods. Research and development testing of a memory design may be performed. Analytics may be gathered from devices operating in the field. Large scale experimentation may be implemented. Machine learning may be employed. Correlations determined through these methodologies may then be used to implement the solution disclosed herein.	188	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	FIG. 8 depicts an example of correlations between memory states 800 and adjustments to read levels for a set of multi-level storage cells of non-volatile memory media. In FIG. 7 a change in threshold voltage for memory cells may result in a shift in the threshold voltages and the corresponding cell threshold voltage distribution(s), e.g., the curves.	189	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	FIG. 8 illustrates another change phenomena for memory cells and the corresponding a cell threshold voltage distribution(s), e.g., the curves. FIG. 8 illustrates that certain memory states may have a correlation to another memory state based on a widening or narrowing of the cell threshold voltage distribution(s), referred to herein as width correlations. Those of still in the art may appreciate that certain non-volatile storage media technologies may, or may not, experience one, or the other, or both of the types of width correlations (widening and narrowing). However, the concepts disclosed and claimed herein apply to non-volatile storage media technologies that experience or one, or the other, or both of the width correlations. "Width correlation" refers to a correlation in which memory cells of a cell threshold voltage distribution within a first memory state change threshold voltage in a manner that widens or narrows a curve representing the cell threshold voltage distribution within the first memory state in response to passage of time, or use of a storage device, in a manner that correlates to a change of threshold voltage in a manner that widens or narrows a curve representing the cell threshold voltage distribution within the second memory state.	190	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	In the example illustrated, adjustments to create adjusted read level B 802, adjusted read level E 804, and adjusted read level G 806 have been made. The previous read levels are also indicated as previous read level B 808, previous read level E 810, and previous read level G 812. The read scan operation, in one embodiment, determines different adjustments to the previous read levels, resulting in the adjusted read levels. The read scan operation may determine adjustment 814, adjustment 816, and adjustment 818 individually for the different memory states B, E, and G, with different magnitudes, different directions, and the like, customizing the different adjustment levels, adjusted read level B 802, adjusted read level E 804, adjusted read level G 806 individually to media characteristics of the different memory states B, E, and G. Each memory state Er, A, B, C, etc., through O as illustrated in FIG. 4 may receive this treatment. A subset of the memory states, Er through G, are illustrated here for convenience. The adjusted read levels align with the changed cell threshold voltage distributions.	191	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	Whereas FIG. 7 illustrated shifting of memory states and shift correlations between memory states, FIG. 8 illustrates an example of correlations between memory states based on a change in width of two cell threshold voltage distributions. Some memory states may exhibit an increasing width 820 while others exhibit a decreasing width (narrowing) 822. In the illustrated example, an increasing width 820 of memory state A 824 may necessitate the adjustment 814 resulting in the adjusted read level B 802. An increasing width 820 in memory state D 826 may similarly result in adjusted read level E 804, whereas a decreasing width (narrowing) 822 of memory state G 830 may yield adjusted read level G 806.	192	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	One may observe that the increasing width 820 of memory state A 824 is frequently accompanied by an increasing width 820 of memory state D 826. These width relationships are one example of a correlation. Specifically, because the increasing width 820 of memory state A 824 occurs in the same direction as the increasing width 820 of memory state D 826, the correlation between them is referred to as a positive width correlation 828.	193	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	One may observe that an increasing width 820 of memory state D 826 is often accompanied by a decreasing width (narrowing) 822 of memory state G 830. This relationship is another example of a correlation. Because the increasing width 820 of memory state D 826 and the decreasing width (narrowing) 822 in memory state G 830 occur in opposite directions, this correlation is referred to as a negative width correlation 832.	194	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	FIG. 9 and FIG. 10 illustrate a shift correlation table 900 and a width correlation table 1000, respectively. One embodiment may use one of or both a shift correlation table 900 and a width correlation table 1000 or a table that combines correlation factors from both. In one embodiment, shift correlation table 900 and width correlation table 1000 store correlation factors which are used to improves read scan operations. Shift correlation table 900 and width correlation table 1000 are but examples of a variety of possible types of correlation data structures that embodiments of the claimed solution may use.	195	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	"Correlation data structure" refers to a data structure configured to store one or more correlation factors and an index for identifying the correlation factor for a particular correlation between two items or things. In one embodiment, a correlation data structure may be a table, an array, a list, a linked list, portion of a memory, a database, or the like. An index for the correlation data structure for correlation factors between memory states may comprise a row identifier for a memory state of correlation data structure table and a correlated memory state may comprise a column of the correlation data structure table.	196	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	In each table, the rows represent a starting memory state and the columns represent an ending memory state for which a correlation exists, that is captured by the correlation factor stored in the cell where the row and column intersect. In one example embodiment, a zero correlation factor may indicate that no correlation, a magnitude of the correlation factor may indicate the strength of the correlation or how much to adjust an attribute (e.g., shift, width, etc.) to account for the correlation, and a positive correlation factor value may represent a positive correlation and a negative correlation factor value may represent a negative correlation.	197	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	Generally, the starting memory state, the row memory state, is a memory state for which an optimal read level has been determined through one or more or parts of a variety of methods. Once that optimal read level is determined for the starting memory state, the shift correlation table 900 and/or width correlation table 1000 may be used to account for the correlation between the starting memory state and the ending memory state and leverage the correlation to determine an optimal read level for the ending memory state.	198	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	By way of example, suppose a starting memory state 902, memory state D, has been determined and a read scan operation is configured to leverage correlations between memory states in determining a read level for an ending memory state 904, memory state G. The read scan operation may consult shift correlation table 900 and locate the row for memory state D and read the value that intersects with the column corresponding to memory state G. The entry is a shift correlation factor 906 and indicates that when starting memory state 902 shifts then, based on a correlation, the ending memory state 904 shifts in an opposite direction, a negative correlation. The negative correlation is indicated by the negative value 150. In this example, the shift correlation factor 906 (e.g., -150 mV as illustrated) may indicate that memory state G experiences a negative shift of 150 mV (shifts down on average voltage by about -150 mV) with respect to memory state D. The read scan operation may leverage this correlation factor to optimize a scanning operation to determine an optimal read level for memory state G.	199	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	FIG. 10 illustrates a width correlation table 1000 having correlation factor that account for width correlations between memory states. As an example, suppose an optimal read level for starting memory state 1002, memory state D, has been determined and a read scan operation is configured to leverage correlations between memory states in determining a read level for an ending memory state 1004, memory state J.	200	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	The read scan operation may consult width correlation table 1000 and locate the row for memory state D and read the value that intersects with the column corresponding to memory state J. The entry is a width correlation factor 1006 and indicates that when starting memory state 1002 widens then, based on a correlation, the ending memory state 1004 also widens by a correlation factor of 1.1016, a positive correlation. The positive correlation is indicated by the positive value greater than 1. In this example, the width correlation factor 1006 (e.g., 1.1016 as illustrated) may indicate that memory state J experiences a widening of 1.1016 times a widening experienced by memory state D. The read scan operation may leverage this correlation factor to optimize a scanning operation to determine an optimal read level for memory state J.	201	Added by DJM 12 2021	12/22/21, 12:00 AM
View Edit Delete	US10998041B1	If a read scan operation determines how a starting memory state (e.g., state D) has shifted or how much the known state widened/narrowed, estimates may be made for other correlated unknown memory states. These estimates may facilitate further read scan operations, or even in certain embodiments, obviate a need for further read scan operations for the ending memory state.	202	Added by DJM 12 2021	12/22/21, 12:00 AM

Page 259 of 438, showing 20 record(s) out of 8,747 total