What does NAND mean, what is NAND

NAND flash.

It is a better storage device than a hard drive, and it is especially evident in low-capacity applications with no more than 4GB. As people continue to pursue products that consume less power, weigh less, and perform better, NAND is proving to be very attractive. NAND flash memory is a non-volatile storage technology that holds data even after a power outage.

Its development goal is to reduce the cost per bit of storage and increase storage capacity.

Electronically refers to AND or Gate!

In layman's terms, it is mobile phone storage Pro explanation: NAND flash memory is a better storage solution than hard drives, which is especially evident in low-capacity applications with no more than 4GB. As people continue to pursue products that consume less power, weigh less, and perform better, NAND is proving to be extremely attractive.

NAND flash arrays are divided into a series of 128KB blocks, which are the smallest erasable entities in NAND devices. Erasing a block is setting all bits to "1" (and all bytes to ffh). It is necessary to programmatically change the erased bits from "1" to "0".

The smallest programming entity is a byte. Some NOR flash memory can perform both read and write operations (see Figure 1 below). While NAND cannot perform both read and write operations at the same time, it can do this at the system level using a method called "shadowing".

This method has been used on PCs for many years, where the BIOS is loaded from a lower rate ROM to a higher rate RAM.

NAND is NAND Gate.

NAND Gate, translated into English as NAND Gate, is a basic logic circuit of digital circuits. When one or more of the inputs are low, the output is high. Only when all inputs are high, the outputs are low.

NAND gates can be seen as superimpositions of AND NAND gates.

The logic gates in CMOS circuits include NAND gates, AND gates, NAND gates, OR gates, XOR gates, XOR gates, XOR gates, Schmitt trigger gates, buffers, drivers, etc.

NAND flash memory is a better storage device than hard drives, and it is especially obvious in low-capacity applications with no more than 4GB; ROM is an abbreviation for ROM Image (Read-Only Memory Image), which is often used in the circle of mobile phone customization system players.

NAND How it works.

Unlike magnetic HDDs, NAND must be in a state where data can be written, and does not have the "write-in-place" function that HDDs have. If the data is already written on the NAND, then the data must be polished to mimic the NAND before the new data can be accepted. Erasing is a process of breaking thin layers of material.

The NAND agency's simple explanation serves to shed some light on this, although it is still confusing.

NAND memory is essentially made up of two types of structures called pages and blocks. Each page is most commonly 4 2 kb (can be of other sizes, but this is the most common) and represents a read and write unit. Multiple pages make up blocks of 32 128 KB or 128 512 KB.

NAND reads and writes are performed at the page level. Instead, erasure is performed at the block level.

ROM definition.

The ROM in the smartphone configuration refers to EEPROM (Electrical Erase Writable Read-Only Memory), which is similar to the hard disk of a computer, and the process of flashing the mobile phone is to write the ROM image to the ROM memory. The ROM of a smart phone refers to its storage space, which is generally made by UFS and other flash memory, and its hardware is not read-only, and the so-called read-only refers to the reading and writing permission settings of the system partition at the software level.

Common ROM images are in IMG, ZIP and other formats, the former is usually flashed in by a fastboot program through a data cable (wire flash), and the latter is usually flashed in from SD in recovery mode (card brush), the solid IMG image is also known as the wire flash package, and the zip image is also known as the card flash package.

Because ROM Image is the most common form of distribution for custom systems, gamers often quietly use the word ROM to refer to the phone's operating system.

Student, do you study microelectronics? To understand NAND chips, it is necessary to understand the structural units inside NAND and NOR memory chips, and understand the floating gate principle, so as to have an in-depth understanding of it.

The features of these two chips mentioned upstairs may not meet your requirements, so I'll add it.

As shown in the figure, NAND was developed later than NOR, in the basic cell structure, NAND is used in the form of thyristors (including floating gate) source and drain end in series, for example, 32 thyristors in series in series are called a block block, erasure and programming must be operated in this minimum unit. As you can see from the diagram, the storage density is greatly increased (although the number of thyristors is not less, and the wiring space is saved). The disadvantages are also obvious, one thyristor is broken, and one block is all broken, so with NAND, there is a lot of error correction to be done in the software, such as ECC

Since each thyristor does not have a separate bit line, the read speed is greatly affected, and the random read speed can only reach 25us (microsecond level).But erasing is faster.

As for NOR, each thyristor (including floating gate) is connected to Bit Line and Word Line, so it can be accessed randomly, and the random read speed can reach 60 70ns (nanosecond level).But the disadvantage of NOR is that it is very slow to erase, and the reason is that it cannot be erased block by block.

This is the basic structural difference, that is, the most basic difference. For example, the NAND interface does not have an address line, while the NOR interface contains a complete address line, which is compatible with SRAM operation. NAND is usually used to store data rather than program files, because program files use a lot of random access, which NAND is not good at.

I have a copy of NAND's information here, it is Toshiba's information, if you need more details, you can find the answer in it, leave an email and I can send it to you

There are two types of flash memory: NOR and NAND. There is a big difference between NOR-type flash memory and NAND flash memory, for example, NOR-type flash memory is more like memory, with independent address lines and data lines, but ** is more expensive and has a smaller capacity; The NAND type is more like a hard disk, the address line and the data line are the same I O line, all the information similar to the hard disk is transmitted through a hard disk line, and the NAND type is lower than the NOR-type flash memory, and the capacity is much larger.

Therefore, NOR-type flash memory is more suitable for frequent random reads and writes, usually used to store programs** and run directly in the flash memory, mobile phones are large users of NOR-type flash memory, so the "memory" capacity of mobile phones is usually not large; NAND flash memory is mainly used to store data, and our commonly used flash memory products, such as flash disks and digital memory cards, are all used NAND flash memory.

NAND chips are chips that use NAND-Flash memory.

NAND-Flash memory is a type of flash memory, which adopts a nonlinear macrocell mode inside, which provides an inexpensive and effective solution for the implementation of solid-state large-capacity memory. Nand-flash memory has the advantages of large capacity and fast rewriting speed, and is suitable for the storage of a large amount of data, so it has been more and more widely used in the industry, such as embedded products including digital cameras, Walkman memory cards, small U disks, etc.

In 1989, Toshiba Corporation published the NAND Flash architecture, emphasizing lower cost per bit, higher performance, and easy interface upgrades like disks.

The pronunciation of nand: 美英 [n nd].

The example sentences are as follows:on the structure of the invalid nand flash, the classified invalid block management algorithm is proposed.Policies are given for invalid block management cores during flash erase, write, and read operations.

of flash file system based on large capacity nand with flash memoryResearch on large-capacity NAND flash file system based on

on the structure of the invalid nand flash, the classified invalid block management algorithm is proposed.Policies are given for invalid block management during flash wipe, write, and read operations.

NAND: All the files required for PSP boot are stored in a chip inside the PSP, and NAND is a physical backup of the contents of this chip, including IPL, IDSachuse, and LFla. Bricks can be repaired with the correct use of a backup NAND, which indicates that PSP never bricks a ROM unless there is hardware damage

There are two types of memory: random access memory (RAM) and read-only memory (ROM). Among them, ROM is usually used to solidify and store some programs or data written by manufacturers, which is used to start the computer and control the working mode of the computer. RAM, on the other hand, is used to access a variety of dynamic input and output data, intermediate calculation results, and data exchanged with external memory and temporary data.

When the device is powered off, the data stored in the RAM is lost.

For mobile phones.

The speed of running games and programs depends on RAM, that is, dynamic memory, not static space, which is used to store things, which is equivalent to the Z drive of the mobile phone. RAM and ROMs are like your computer's memory and hard drive. To be precise, a C drive should not be called a ROM read-only memory.

The C drive should be called Flash, because the C drive is rewritable, and the size of the flash does not affect the running speed.