Sandisk Patent Applications

NAND MEMORY WITH DIFFERENT PASS VOLTAGE RAMP RATES FOR BINARY AND MULTI-STATE MEMORY

Granted: February 29, 2024
Application Number: 20240071544
To reduce spikes in the current used by a NAND memory die, different ramp rates are used for the pass voltage applied to unselected word lines during a program operation depending on whether data is stored in a multi-level cell (MLC) format or in a single level cell (SLC) format. These ramp rates can be determined through device characterization and stored as parameter values on the memory die. Different ramp rate interval values can also be used for the pass voltage applied to…

NON-VOLATILE MEMORY WITH TIER-WISE RAMP DOWN AFTER PROGRAM-VERIFY

Granted: February 29, 2024
Application Number: 20240071529
Memory cells are arranged as NAND strings to form a block divided into sub-blocks, and each NAND string includes a dummy memory cell connected to a dummy word line. Memory cells are programmed by applying programming pulses to a selected word line in a selected sub-block with program-verify performed between pulses. Unselected NAND strings are inhibited from programming by boosting channels of the unselected NAND strings in the selected sub-block from a positive pre-charge voltage to a…

IN-PLACE WRITE TECHNIQUES WITHOUT ERASE IN A MEMORY DEVICE

Granted: February 29, 2024
Application Number: 20240071508
The memory device includes a plurality of memory blocks, each including a plurality of memory cells arranged in a plurality of word lines. Control circuitry is in communication with the plurality of memory blocks. In operation, the control circuitry receives a data write instruction and programs the memory cells of the memory blocks to a one bit per memory cell (SLC) format. In response to the data programmed to the memory cells of the memory blocks in the SLC format reaching an SLC…

NON-VOLATILE MEMORY WITH EARLY DUMMY WORD LINE RAMP DOWN AFTER PRECHARGE

Granted: February 15, 2024
Application Number: 20240055059
Non-volatile memory cells are programmed by pre-charging channels of unselected non-volatile memory cells connected to a selected data word line, boosting the channels of unselected non-volatile memory cells connected to the selected data word line after the pre-charging and applying a program voltage pulse to selected non-volatile memory cells connected to the selected data word line while boosting. The pre-charging includes applying pre-charge voltages to one set of data word lines and…

DYNAMIC WORD LINE RECONFIGURATION FOR NAND STRUCTURE

Granted: February 15, 2024
Application Number: 20240055051
Technology is disclosed herein reconfiguring word lines as either data word lines or dummy word lines. In a sub-block mode reconfigurable word lines are used as dummy word lines that provide electrical isolation between data word lines in a block. The block may be divided into an upper tier, a middle tier, and a lower tier, with the reconfigurable word lines within the middle tier. In a full-block mode the reconfigurable group of the word lines are used as data word lines. Because the…

NON-VOLATILE MEMORY WITH NARROW AND SHALLOW ERASE

Granted: February 8, 2024
Application Number: 20240046996
In a non-volatile memory, to achieve a shallow and tight erased threshold voltage distribution, a process is performed that includes erasing a group of non-volatile memory cells, identifying a first set of the bit lines that are connected to non-volatile memory cells of the group that are erased past a lower limit for erased non-volatile memory cells and identifying a second set of the bit lines that are connected to non-volatile memory cells of the group that are not erased past the…

NON-VOLATILE MEMORY WITH OPTIMIZED ERASE VERIFY SEQUENCE

Granted: February 8, 2024
Application Number: 20240047000
An erase process for a group of non-volatile memory cells comprises applying doses of erasing to the group and performing erase verify between pairs of successive doses of erasing. The time needed to complete the erase process can be reduced by optimizing the order of performing erase verify. For example, erase verify can be performed by separately performing erase verify for multiple portions of the group in order from previously determined slowest erasing portion of the group to…

NON-VOLATILE MEMORY WITH NARROW AND SHALLOW ERASE

Granted: February 8, 2024
Application Number: 20240046996
In a non-volatile memory, to achieve a shallow and tight erased threshold voltage distribution, a process is performed that includes erasing a group of non-volatile memory cells, identifying a first set of the bit lines that are connected to non-volatile memory cells of the group that are erased past a lower limit for erased non-volatile memory cells and identifying a second set of the bit lines that are connected to non-volatile memory cells of the group that are not erased past the…

NON-VOLATILE MEMORY WITH OPTIMIZED ERASE VERIFY SEQUENCE

Granted: February 8, 2024
Application Number: 20240047000
An erase process for a group of non-volatile memory cells comprises applying doses of erasing to the group and performing erase verify between pairs of successive doses of erasing. The time needed to complete the erase process can be reduced by optimizing the order of performing erase verify. For example, erase verify can be performed by separately performing erase verify for multiple portions of the group in order from previously determined slowest erasing portion of the group to…

NON-VOLATILE MEMORY WITH OPTIMIZED OPERATION SEQUENCE

Granted: February 1, 2024
Application Number: 20240036740
A non-volatile memory system separately performs a memory operation for multiple sub-blocks of a block in order from previously determined slowest sub-block of the block to a previously determined faster sub-block of the block. As a slower sub-block is more likely to fail, this order of is more likely to identify a failure earlier in the process thereby saving time and reducing potential for a disturb. In some embodiments, the proposed order of operation can be used in conjunction with a…

EARLY DETECTION OF PROGRAMMING FAILURE FOR NON-VOLATILE MEMORY

Granted: February 1, 2024
Application Number: 20240038315
An apparatus is provided that includes a block including a word line coupled to a plurality of memory cells, and a control circuit coupled to the word line. The control circuit is configured to program the plurality of memory cells by applying program pulses to the word line in a plurality of program loops, determining a first count of a number of the program loops used to complete programming a first subset of the plurality of memory cells to a first programmed state, first comparing…

EARLY DETECTION OF PROGRAMMING FAILURE FOR NON-VOLATILE MEMORY

Granted: February 1, 2024
Application Number: 20240038315
An apparatus is provided that includes a block including a word line coupled to a plurality of memory cells, and a control circuit coupled to the word line. The control circuit is configured to program the plurality of memory cells by applying program pulses to the word line in a plurality of program loops, determining a first count of a number of the program loops used to complete programming a first subset of the plurality of memory cells to a first programmed state, first comparing…

NON-VOLATILE MEMORY WITH OPTIMIZED OPERATION SEQUENCE

Granted: February 1, 2024
Application Number: 20240036740
A non-volatile memory system separately performs a memory operation for multiple sub-blocks of a block in order from previously determined slowest sub-block of the block to a previously determined faster sub-block of the block. As a slower sub-block is more likely to fail, this order of is more likely to identify a failure earlier in the process thereby saving time and reducing potential for a disturb. In some embodiments, the proposed order of operation can be used in conjunction with a…

MEMORY DIE HAVING A UNIQUE STORAGE CAPACITY

Granted: January 25, 2024
Application Number: 20240029789
The memory die that includes a plurality of memory blocks. Each memory block includes a plurality of memory cells that are configured to store three bits of data in each memory cell when the memory die is in a TLC operating mode. The memory die has a non-binary data capacity, which is a multiple of 683 Gb, when the memory die is operating in the TLC operating mode.

ADAPTIVE FAIL BITS THRESHOLD NUMBER FOR ERASING NON-VOLATILE MEMORY

Granted: January 25, 2024
Application Number: 20240029804
An apparatus is provided that includes a block of memory cells and a control circuit coupled to the block of memory cells. The control circuit is configured to perform an erase operation on the block of memory cells by determining a first count of a number of times that the block of memory cells previously has been programmed and erased, determining a threshold number based on the first count, and determining whether the erase operation passed or failed based on the threshold number.

NON-VOLATILE MEMORY WITH ONE SIDED PHASED RAMP DOWN AFTER PROGRAM-VERIFY

Granted: January 25, 2024
Application Number: 20240029806
In a non-volatile memory system that performs programming of selected memory cells (in coordination with pre-charging and boosting of channels for unselected memory cells) and program-verify to determine whether the programming was successful, the system transitions from program-verify to the next dose of programming by concurrently lowering a voltage applied to a selected word line and voltages applied to word lines on a first side of the selected word line at the conclusion of…

NON-VOLATILE MEMORY WITH ONE SIDED PHASED RAMP DOWN AFTER PROGRAM-VERIFY

Granted: January 25, 2024
Application Number: 20240029806
In a non-volatile memory system that performs programming of selected memory cells (in coordination with pre-charging and boosting of channels for unselected memory cells) and program-verify to determine whether the programming was successful, the system transitions from program-verify to the next dose of programming by concurrently lowering a voltage applied to a selected word line and voltages applied to word lines on a first side of the selected word line at the conclusion of…

ADAPTIVE FAIL BITS THRESHOLD NUMBER FOR ERASING NON-VOLATILE MEMORY

Granted: January 25, 2024
Application Number: 20240029804
An apparatus is provided that includes a block of memory cells and a control circuit coupled to the block of memory cells. The control circuit is configured to perform an erase operation on the block of memory cells by determining a first count of a number of times that the block of memory cells previously has been programmed and erased, determining a threshold number based on the first count, and determining whether the erase operation passed or failed based on the threshold number.

MEMORY DIE HAVING A UNIQUE STORAGE CAPACITY

Granted: January 25, 2024
Application Number: 20240029789
The memory die that includes a plurality of memory blocks. Each memory block includes a plurality of memory cells that are configured to store three bits of data in each memory cell when the memory die is in a TLC operating mode. The memory die has a non-binary data capacity, which is a multiple of 683 Gb, when the memory die is operating in the TLC operating mode.

NON-VOLATILE MEMORY WITH SUSPENSION PERIOD DURING PROGRAMMING

Granted: January 4, 2024
Application Number: 20240006002
To remedy short term data retention issues, a system creates a gate to channel voltage differential for non-volatile memory cells between programming and verifying in order to accelerate the effects of the short term data retention issue. That is, the gate to channel voltage differential will accelerate the migrating of electrons out of shallow traps. In some embodiments, the gate to channel voltage differential comprises a higher voltage at the channel in comparison to the gate. In some…