Flash memory is a form of semi-pass technology and electrical reprogrammable memory. The same concept can be used in electronic circuitry to denote technologically complete solutions. In everyday life, this concept is fixed for a wide class of solid-state devices for storing information.
Necessary
USB flash drive, a computer with an Internet connection
Instructions
Step 1
The principle of operation of this technology is based on changes and registrations in isolated areas of electric charge in a semiconductor structure. The change of such a charge, that is, its recording and erasure, occurs with the help of an application located between the source and the gate of its greater potential. Thus, a sufficient electric field strength is created between the transistor and the pocket in a thin dielectric field. This is how the tunneling effect arises.
Step 2
Memory resources are based on charge change. It is sometimes associated with the cumulative effect of irreversible phenomena in its structure. Therefore, the number of entries is limited for the flash cell. This figure for the MLC is usually 10 thousand units, and for the SLC it is up to 100 thousand units.
Step 3
Data retention time is determined by how long the charges are stored, which is usually stated by most household product manufacturers. It does not exceed ten to twenty years. Although the manufacturers only give a guarantee for the first five years. It should be noted, however, that MLC devices have shorter data retention periods than SLC devices.
Step 4
The hierarchical structure of flash memory is explained by the following fact. Processes such as writing and erasing, as well as reading information from a flash drive, occur in large blocks of different sizes. For example, an erase block is larger than a write block, which in turn is smaller than a read block. This is a distinctive feature of flash memory from the classic one. As a result, all of its microcircuits have a pronounced hierarchical structure. The memory is thus divided into blocks, and those into sectors and pages.
Step 5
The speed of erasing, reading and writing is different. For example, the erasure speed can vary from one to hundreds of milliseconds. It depends on the size of the information being erased. The recording speed is tens or hundreds of microseconds. The reading speed is usually tens of nanoseconds.
Step 6
Features of the use of flash memory are dictated by its features. It is allowed to produce and sell microcircuits with any number of defective memory cells. To make this percentage lower, each page is supplied with small additional blocks.
Step 7
The weak point of flash memory is that the number of rewriting cycles on one page is limited. The situation becomes even worse due to the fact that file systems often write to the same memory location.
