Method, device and equipment for quickly searching VT trough based on SHIFT READ and medium

Abstract

The embodiment of the invention discloses a method, device and equipment for quickly searching a VT trough based on SHIFT READ and a medium, and relates to the technical field of solid state disks. The method comprises the following steps: reading data of a Nand Flash according to a preset reference voltage to obtain first data; performing offset reading on the data of the Nand Flash with a plurality of preset offset voltages to obtain a plurality of second data; performing exclusive-or operation on the plurality of second data and the first data to obtain a calculation result; and determining the optimal read voltage of the Nand Flash based on the calculation result. According to the method, the optimal read voltage can be quickly confirmed based on finite offset reading, and compared with a mode based on rereading a parameter table in the prior art, the efficiency is higher; and after the optimal read voltage is confirmed, the data of the Nand Flash is read by adopting the optimal read voltage subsequently, so that the data bit flipping can be effectively reduced, the data loss caused by the UNC is avoided, the service life of the block is prolonged, and the stable operation of the SSD service is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of solid-state drives, and in particular, to a method, device, equipment and medium for quickly finding the VT trough based on SHIFT READ. Background Art

[0002] In the field of NAND flash memory storage technology, after the data storage unit completes the write operation, its charge state is vulnerable to multiple factors such as environmental temperature fluctuations, working voltage deviations, and storage time lapse, resulting in a shift in the voltage threshold (VT). This change in physical characteristics will directly affect the accuracy of data reading. If the default reference voltage is still used for the reading operation, the actual charge distribution of the storage unit may deviate from the expected range, causing a significant increase in the number of error bits (FBC) during the reading process. When the FBC exceeds the error correction capacity of the low-density parity-check (LDPC) engine, it will ultimately lead to unrecoverable data (UNC) errors, seriously threatening the reliability of the storage device.

[0003] Traditional solutions generally rely on the read retry parameter table pre-set by the storage particle manufacturer, and try to recover data by gradually adjusting the reading voltage threshold. This solution needs to traverse all the predefined voltage levels until the FBC drops within the error correction threshold or all levels are tried. However, the design of such parameter tables is usually based on the charge distribution model under a specific test environment, and there are adaptation limitations in actual complex working conditions. Especially in the scenario of abnormal charge distribution, the traversal voltage adjustment will significantly extend the error correction time, resulting in a cliff-like decline in the read and write performance of the solid-state storage device (SSD), seriously affecting the stability of the business system. Summary of the Invention

[0004] Embodiments of the present invention provide a method, device, equipment and medium for quickly finding the VT trough based on SHIFT READ, aiming to solve at least one of the technical problems in the above background art.

[0005] In a first aspect, embodiments of the present invention provide a method for quickly finding the VT trough based on SHIFT READ, which includes:

[0006] Reading the data of the Nand Flash with a preset reference voltage to obtain the first data;

[0007] Performing offset reading on the data of the Nand Flash with a preset plurality of offset voltages to obtain a plurality of second data;

[0008] Performing exclusive OR operations on the plurality of second data and the first data respectively to obtain calculation results;

[0009] Determine the optimal read voltage of the Nand Flash based on the calculation result.

[0010] A further technical solution thereof is that, among the multiple offset voltages, the number of offset voltages greater than the reference voltage is the same as the number of offset voltages less than the reference voltage.

[0011] A further technical solution thereof is that the number of the offset voltages does not exceed 6.

[0012] A further technical solution thereof is that the step of respectively performing exclusive OR operations on the multiple second data and the first data to obtain a calculation result includes:

[0013] Respectively perform exclusive OR operations on the multiple second data and the first data, count the number of 1s to obtain the calculation result.

[0014] A further technical solution thereof is that the step of determining the optimal read voltage of the Nand Flash based on the calculation result includes:

[0015] Perform curve fitting with the offset voltage in the calculation result as the abscissa and the number of 1s corresponding to the offset voltage as the ordinate to obtain a target curve;

[0016] Determine the optimal read voltage of the Nand Flash based on the target curve.

[0017] A further technical solution thereof is that the step of determining the optimal read voltage of the Nand Flash based on the target curve includes:

[0018] Obtain the lowest point of the target curve;

[0019] Obtain the voltage value corresponding to the lowest point as the optimal read voltage.

[0020] A further technical solution thereof is that the method further includes:

[0021] Read the data of the Nand Flash with the optimal read voltage.

[0022] In a second aspect, an embodiment of the present invention further provides a device for quickly finding the VT trough based on SHIFT READ, which includes units for executing the above method.

[0023] In a third aspect, an embodiment of the present invention further provides a computer device, which includes a memory and a processor, and a computer program is stored on the memory, and when the processor executes the computer program, the above method is implemented.

[0024] Fourthly, an embodiment of the present invention further provides a computer-readable storage medium storing a computer program, which can implement the above method when executed by a processor.

[0025] An embodiment of the present invention provides a method, device, equipment and medium for quickly finding the VT trough based on SHIFT READ. Among them, the method includes: reading the data of the Nand Flash with a preset reference voltage to obtain the first data; performing offset reading on the data of the Nand Flash with a plurality of preset offset voltages to obtain a plurality of second data; respectively performing exclusive OR operations on the plurality of second data and the first data to obtain calculation results; determining the optimal read voltage of the Nand Flash based on the calculation results. The present invention can quickly confirm the optimal read voltage based on a limited number of offset readings, and has higher efficiency compared with the method based on re-reading the parameter table in the prior art; after confirming the optimal read voltage, the subsequent use of the optimal read voltage to read the data of the Nand Flash can effectively reduce the data bit flip, avoid data loss caused by UNC, extend the service life of the block, and is beneficial to the stable operation of the SSD service. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 It is a schematic flow chart of a method for quickly finding the VT trough based on SHIFT READ provided by an embodiment of the present invention;

[0028] Figure 2 It is a schematic principle diagram of a method for quickly finding the VT trough based on SHIFT READ provided by a specific embodiment of the present invention;

[0029] Figure 3 It is a schematic block diagram of a computer device provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0031] It should be understood that when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0032] It should also be understood that the terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. As used in this specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0033] It should be further understood that the term "and / or" used in this specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0034] As used in this specification and the appended claims, the term "if" can be interpreted as "when", "once", "in response to determining", or "in response to detecting" according to the context. Similarly, the phrases "if determined" or "if [the described condition or event] is detected" can be interpreted as meaning "once determined", "in response to determining", "once [the described condition or event] is detected", or "in response to detecting [the described condition or event]" according to the context.

[0035] Please refer to Figure 1 , an embodiment of the present invention provides a method for quickly finding the VT trough based on SHIFT READ. The method includes the following steps:

[0036] S1, read the data of the Nand Flash with a preset reference voltage to obtain first data.

[0037] In specific implementation, the reference voltage refers to the voltage for reading the Nand Flash set in advance. The reference voltage can be set by those skilled in the art, and the present invention does not specifically limit this.

[0038] In an embodiment of the present invention, first, the data of the Nand Flash is read with a preset reference voltage to obtain first data.

[0039] S2, perform offset reading on the data of the Nand Flash with a preset plurality of offset voltages to obtain a plurality of second data.

[0040] In specific implementation, a plurality of offset voltages are preset in advance. The offset voltages are obtained by increasing / decreasing the reference voltage. The data of the Nand Flash are respectively subjected to offset read (SHIFT READ) with the plurality of offset voltages to obtain a plurality of second data, that is, one offset voltage corresponds to one second data read.

[0041] Specifically, in the embodiment of the present invention, among the plurality of offset voltages, the number of offset voltages greater than the reference voltage is the same as the number of offset voltages less than the reference voltage, and the situations of left and right offsets can be considered simultaneously to ensure the accuracy of subsequent optimal read voltage determination. The number of the offset voltages does not exceed 6. For example, in this embodiment, it is 4. Setting the offset voltages not exceeding 6 can reduce the subsequent calculation amount and improve the efficiency.

[0042] S3. Respectively perform exclusive OR operations on the plurality of second data and the first data to obtain calculation results.

[0043] In specific implementation, respectively perform exclusive OR operations on the plurality of second data and the first data, and count the number of 1s to obtain the calculation results. That is, respectively count the number of 1s obtained by performing exclusive OR operations on each second data and the first data.

[0044] In the specific implementation process, the following core operations are performed:

[0045] 1. Reference data anchoring

[0046] Select a reference voltage (denoted as V1st) to perform the first data read on the storage unit to obtain a reference data set D_base.

[0047] 2. Differential comparison mechanism

[0048] For each offset voltage Vx (such as V2nd, V3rd, etc.), perform the following operations:

[0049] Voltage offset read operation: Apply the Vx voltage to perform a second read on the storage unit to obtain the corresponding data set Dx.

[0050] Bit-level difference detection: Perform a bit-by-bit exclusive OR (XOR) operation on Dx and D_base. This operation is essentially a binary difference amplifier: when two data bits are the same, it outputs 0, and when they are different, it outputs 1. For example:

[0051] In an embodiment, D_base: 010110; Dx: 001100; XOR result: 011010 → count that "1" appears 3 times.

[0052] Difference quantization statistics: Traverse the entire data set and accumulate the number of occurrences of "1" in the XOR result.

[0053] S4. Determine the optimal read voltage of the Nand Flash based on the calculation result.

[0054] In specific implementation, determine the optimal read voltage of the Nand Flash based on the calculation result.

[0055] For example, it specifically includes the following steps: Use the offset voltage in the calculation result as the abscissa and the number of 1s corresponding to the offset voltage as the ordinate for curve fitting to obtain the target curve; Determine the optimal read voltage of the Nand Flash based on the target curve.

[0056] In specific implementation, those skilled in the art can adopt curve fitting methods such as quadratic polynomial fitting, Gaussian mixture model fitting, cubic spline interpolation, or other curve fitting methods. The present invention does not specifically limit this.

[0057] In some embodiments, the above step "Determine the optimal read voltage of the Nand Flash based on the target curve" includes: Obtain the lowest point of the target curve; Obtain the voltage value corresponding to the lowest point as the optimal read voltage.

[0058] In specific implementation, analyze the target curve to obtain the lowest point of the target curve, and use the voltage value corresponding to the lowest point as the optimal read voltage. Specifically, the lowest point represents that the trend of 0,1 bit flipping is the smallest at this time, which means that the FBC read with this voltage is the smallest. Therefore, the voltage value corresponding to the lowest point is the optimal read voltage.

[0059] Furthermore, the method further includes: Read the data of the Nand Flash with the optimal read voltage.

[0060] In specific implementation, after confirming the optimal read voltage, reading the data of the Nand Flash with the optimal read voltage can effectively reduce data bit flipping, avoid data loss caused by UNC, extend the service life of the block, and is beneficial to the stable operation of the SSD service.

[0061] See Figure 2 , Figure 2 shows the implementation process of a specific embodiment of the present invention. Among them, 1st is the reference voltage, and 5th, 3rd, 2nd, 4th are offset voltages. It specifically includes the following steps:

[0062] 1. Read with the voltage at the position of 1st to obtain a piece of data;

[0063] 2. Read with the voltage at the position of 2nd as the offset voltage to obtain a piece of data, and at the same time perform exclusive OR with this piece of data of 1st to count the number of 1s;

[0064] 3. Read the offset voltage at the voltage of the 4th position to obtain a piece of data, and at the same time perform exclusive OR with this piece of data of the 1st, and count the number of 1s;

[0065] 4. Read the offset voltage at the voltage of the 3rd position to obtain a piece of data, and at the same time perform exclusive OR with this piece of data of the 1st, and count the number of 1s;

[0066] 5. Read the offset voltage at the voltage of the 5th position to obtain a piece of data, and at the same time perform exclusive OR with this piece of data of the 1st, and count the number of 1s;

[0067] 6. Using the number of 1s obtained 4 times, form a histogram with the number of 1s in the order of 5th, 3rd, 2nd, and 4th, perform curve fitting, and the voltage value corresponding to the lowest point obtained is the optimal read voltage.

[0068] It can be seen that by performing exclusive OR on the data read by multiple offsets and the data read by the 1st, the number of 0,1 flips can be obtained. According to the change trend of this number of 0,1 flips, the optimal voltage position can be obtained. For example, if the left side of the 1st is 1 and the right side is 0, when reading with the 5th and 3rd positions, some 1s will become 0, and when reading with the 2nd and 4th positions, 0s will become 1. Then, the trend from 1→0→1 can be curve-fitted, and the lowest point of this trend is the optimal voltage position.

[0069] An embodiment of the present invention proposes a method for quickly finding the VT trough based on SHIFT READ, including: reading the data of the Nand Flash with a preset reference voltage to obtain the first data; performing offset reading on the data of the Nand Flash with a preset plurality of offset voltages to obtain a plurality of second data; respectively performing exclusive OR operations on the plurality of second data and the first data to obtain calculation results; determining the optimal read voltage of the Nand Flash based on the calculation results. The present invention can quickly confirm the optimal read voltage based on a limited number of offset readings, and has higher efficiency compared to the method based on re-reading the parameter table in the prior art; after confirming the optimal read voltage, subsequently reading the data of the Nand Flash with the optimal read voltage can effectively reduce data bit flipping, avoid data loss caused by UNC, extend the block service life, and is beneficial to the stable operation of the SSD service.

[0070] Corresponding to the above method for quickly finding the VT trough based on SHIFT READ, the present invention also provides a device for quickly finding the VT trough based on SHIFT READ. The device for quickly finding the VT trough based on SHIFT READ includes a unit for executing the above method for quickly finding the VT trough based on SHIFT READ, and the device for quickly finding the VT trough based on SHIFT READ can be configured in terminals such as desktop computers, tablet computers, laptop computers, etc. Specifically, the device for quickly finding the VT trough based on SHIFT READ includes;

[0071] A reference reading unit for reading the data of the Nand Flash with a preset reference voltage to obtain first data;

[0072] An offset reading unit for performing offset reading on the data of the Nand Flash with a plurality of preset offset voltages to obtain a plurality of second data;

[0073] An operation unit for respectively performing exclusive OR operations on the plurality of second data and the first data to obtain a calculation result;

[0074] A determination unit for determining the optimal read voltage of the Nand Flash based on the calculation result.

[0075] In some embodiments, such as this embodiment, among the plurality of offset voltages, the number of offset voltages greater than the reference voltage is the same as the number of offset voltages less than the reference voltage.

[0076] In some embodiments, such as this embodiment, the number of the offset voltages does not exceed 6.

[0077] In some embodiments, such as this embodiment, the step of respectively performing exclusive OR operations on the plurality of second data and the first data to obtain a calculation result includes:

[0078] Respectively performing exclusive OR operations on the plurality of second data and the first data, and counting the number of 1s to obtain the calculation result.

[0079] In some embodiments, such as this embodiment, the step of determining the optimal read voltage of the Nand Flash based on the calculation result includes:

[0080] Performing curve fitting with the offset voltage in the calculation result as the abscissa and the number of 1s corresponding to the offset voltage as the ordinate to obtain a target curve;

[0081] Determining the optimal read voltage of the Nand Flash based on the target curve.

[0082] In some embodiments, such as this embodiment, determining the optimal read voltage of the Nand Flash based on the target curve includes:

[0083] Obtain the lowest point of the target curve;

[0084] Obtain the voltage value corresponding to the lowest point as the optimal read voltage.

[0085] In some embodiments, such as this embodiment, the device for quickly finding the VT trough based on SHIFT READ further includes:

[0086] Read the data of the Nand Flash with the optimal read voltage.

[0087] It should be noted that those skilled in the art can clearly understand that the specific implementation processes of the above device for quickly finding the VT trough based on SHIFT READ and each unit can refer to the corresponding descriptions in the foregoing method embodiments. For the sake of convenience and conciseness of description, they will not be elaborated here.

[0088] The above device for quickly finding the VT trough based on SHIFT READ can be implemented in the form of a computer program, and this computer program can run on a computer device as shown in Figure 3 shown.

[0089] Please refer to Figure 3 , Figure 3 which is a schematic block diagram of a computer device provided by an embodiment of the present application. The computer device 500 can be a terminal or a server. Among them, the terminal can be an electronic device with communication functions such as a smart phone, a tablet computer, a notebook computer, a desktop computer, a personal digital assistant, and a wearable device. The server can be an independent server or a server cluster composed of multiple servers.

[0090] The computer device 500 includes a processor 502, a memory, and a network interface 505 connected through a system bus 501. Among them, the memory can include a non-volatile storage medium 503 and an internal memory 504.

[0091] The non-volatile storage medium 503 can store an operating system 5031 and a computer program 5032. When the computer program 5032 is executed, the processor 502 can be made to execute a method for quickly finding the VT trough based on SHIFT READ.

[0092] The processor 502 is used to provide computing and control capabilities to support the operation of the entire computer device 500.

[0093] The internal memory 504 provides an environment for the operation of the computer program 5032 in the non-volatile storage medium 503. When the computer program 5032 is executed by the processor 502, the processor 502 can be made to execute a method for quickly finding the VT trough based on SHIFT READ.

[0094] The network interface 505 is used for network communication with other devices. Those skilled in the art can understand that the above structure is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device 500 to which the solution of this application is applied. Specifically, the computer device 500 may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0095] Among them, the processor 502 is used to run the computer program 5032 stored in the memory to implement a method for quickly finding the VT trough based on SHIFT READ provided in any of the above embodiments, specifically including the following steps:

[0096] Read the data of the Nand Flash with a preset reference voltage to obtain the first data;

[0097] Perform offset reads on the data of the Nand Flash with a plurality of preset offset voltages to obtain a plurality of second data;

[0098] Perform exclusive OR operations on the plurality of second data and the first data respectively to obtain a calculation result;

[0099] Determine the optimal read voltage of the Nand Flash based on the calculation result.

[0100] In some embodiments, such as this embodiment, among the plurality of offset voltages, the number of offset voltages greater than the reference voltage is the same as the number of offset voltages less than the reference voltage.

[0101] In some embodiments, such as this embodiment, the number of offset voltages does not exceed 6.

[0102] In some embodiments, such as this embodiment, the performing exclusive OR operations on the plurality of second data and the first data respectively to obtain a calculation result includes:

[0103] Perform exclusive OR operations on the plurality of second data and the first data respectively, count the number of 1s, and obtain the calculation result.

[0104] In some embodiments, such as this embodiment, the determining the optimal read voltage of the Nand Flash based on the calculation result includes:

[0105] Using the offset voltage in the calculation result as the abscissa and the number of 1s corresponding to the offset voltage as the ordinate for curve fitting to obtain a target curve;

[0106] Based on the target curve, determine the optimal read voltage of the Nand Flash.

[0107] In some embodiments, such as this embodiment, the determining the optimal read voltage of the Nand Flash based on the target curve includes:

[0108] Obtain the lowest point of the target curve;

[0109] Obtain the voltage value corresponding to the lowest point as the optimal read voltage.

[0110] In some embodiments, such as this embodiment, the method further includes:

[0111] Read the data of the Nand Flash with the optimal read voltage.

[0112] It should be understood that in the embodiments of the present application, the processor 502 may be a central processing unit (CPU), and this processor 502 may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0113] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a storage medium, and the storage medium is a computer-readable storage medium. The computer program is executed by at least one processor in the computer system to implement the process steps of the embodiments of the above methods.

[0114] Therefore, the present invention also provides a storage medium. The storage medium can be a computer-readable storage medium. The storage medium stores a computer program. When the computer program is executed by a processor, the processor executes a method for quickly finding the VT trough based on SHIFT READ provided in any of the above embodiments, specifically including the following steps:

[0115] Read the data of the Nand Flash with a preset reference voltage to obtain the first data;

[0116] Perform offset reading on the data of the Nand Flash with a plurality of preset offset voltages to obtain a plurality of second data;

[0117] Exclusive-OR each of the plurality of second data with the first data respectively to obtain a calculation result;

[0118] Determine the optimal read voltage of the Nand Flash based on the calculation result.

[0119] In some embodiments, such as this embodiment, among the plurality of offset voltages, the number of offset voltages greater than the reference voltage is the same as the number of offset voltages less than the reference voltage.

[0120] In some embodiments, such as this embodiment, the number of the offset voltages does not exceed 6.

[0121] In some embodiments, such as this embodiment, the step of exclusive-OR each of the plurality of second data with the first data respectively to obtain a calculation result includes:

[0122] Exclusive-OR each of the plurality of second data with the first data respectively, count the number of 1s to obtain the calculation result.

[0123] In some embodiments, such as this embodiment, the step of determining the optimal read voltage of the Nand Flash based on the calculation result includes:

[0124] Perform curve fitting with the offset voltage in the calculation result as the abscissa and the number of 1s corresponding to the offset voltage as the ordinate to obtain a target curve;

[0125] Determine the optimal read voltage of the Nand Flash based on the target curve.

[0126] In some embodiments, such as this embodiment, the step of determining the optimal read voltage of the Nand Flash based on the target curve includes:

[0127] Obtain the lowest point of the target curve;

[0128] Obtain the voltage value corresponding to the lowest point as the optimal read voltage.

[0129] In some embodiments, such as this embodiment, the method further includes:

[0130] Read the data of the Nand Flash with the optimal read voltage.

[0131] The storage medium is a physical, non-transitory storage medium, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a magnetic disk, or an optical disc, etc., which are all physical storage media that can store program codes. The computer-readable storage medium can be non-volatile or volatile.

[0132] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0133] In several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of each unit is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0134] The steps in the method embodiments of the present invention can be adjusted, combined, and deleted according to actual needs. The units in the device embodiments of the present invention can be combined, divided, and deleted according to actual needs. In addition, the functional units in each embodiment of the present invention can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit.

[0135] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a terminal, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present invention.

[0136] In the above embodiments, the descriptions of each embodiment have their own emphases. For the parts not detailedly described in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0137] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

[0138] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for quickly finding VT trough based on SHIFT READ, characterized in that: include: Reading data of Nand Flash with a preset reference voltage to obtain first data; Performing offset reading on the data of the Nand Flash with a plurality of preset offset voltages to obtain a plurality of second data; performing an exclusive OR operation on each of the plurality of the second data and the first data to obtain a calculation result; An optimal read voltage of the Nand Flash is determined based on the calculation result.

2. The method for quickly finding VT trough based on SHIFT READ according to claim 1, characterized in that: Among the plurality of offset voltages, the number of offset voltages greater than the reference voltage is the same as the number of offset voltages less than the reference voltage.

3. The method for quickly finding VT trough based on SHIFT READ according to claim 1, characterized in that: The number of the offset voltages does not exceed 6.

4. The method for quickly finding VT trough based on SHIFT READ according to claim 1, characterized in that: The performing an XOR operation on the plurality of second data and the first data respectively to obtain a calculation result includes: Perform an XOR operation on the plurality of second data and the first data respectively, count the number of 1s, and obtain the calculation result.

5. The method for quickly finding VT trough based on SHIFT READ according to claim 4, characterized in that: The determining the optimal read voltage of the Nand Flash based on the calculation result includes: Based on the offset voltage in the calculation result as the horizontal coordinate and the number of 1s corresponding to the offset voltage as the vertical coordinate, a curve fitting is performed to obtain a target curve; Based on the target curve, an optimal read voltage of the Nand Flash is determined.

6. The method for quickly finding VT trough based on SHIFT READ according to claim 5, characterized in that: The determining the optimal read voltage of the Nand Flash based on the target curve includes: Obtaining the lowest point of the target curve; A voltage value corresponding to the lowest point is obtained as the optimal reading voltage.

7. The method for quickly finding VT trough based on SHIFT READ according to claim 1, characterized in that: The method further comprises: The data of the Nand Flash is read with the optimal read voltage.

8. A device for quickly finding VT trough based on SHIFT READ, characterized in that: The method comprises a unit for executing the method according to any one of claims 1 to 7.

9. A computer device, characterized in that: The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the method according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 can be implemented.

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