#750 What's Flash Memory? > 자유게시판

What is flash memory? It's a type of Memory Wave that may retailer data with out power and may erase memory in blocks. It is a kind of electronically erasable programmable learn solely memory (EEPROM). Computer systems store data on their memory chips in binary, which implies every thing is decreased to a 1 and a 0. When the computer desires to read the information, it scans the memory chip and interprets the 1s and the 0s back into something that we are able to read, or an image or a movie. Every character you are reading has been rendered from binary. However, the computer doesn’t actually store the information as 1s and 0s. There are three different strategies it makes use of. The first technique is in random access memory where the data is stored utilizing electrons. A memory chip is made up of billions of capacitors. These capacitors are in a position to carry electrons. If a capacitor is holding electrons, then it's a 1 and if a capacitor is empty of electrons, then it is a 0. A single capacitor is a bit of information and there are eight bits in a byte, so a byte has eight capacitors.

"Hello" has forty different bits of knowledge, which is 5 bytes. A 16-gigabyte memory card has 128 billion capacitors. The capacitors cannot hold the electrons when the computer is turned off, so RAM is only usable when the pc has power. The second manner is on the laborious disk drive where the information is stored magnetically. The pc has a spinning hard disk and it shops the knowledge on it by marking microscopic lines that are magnetic. When the computer reads the data, each magnetic line is taken into account a 1 and each nonmagnetic line is taken into account a 0. The third method uses transistors to hold a charge and that is how flash Memory Wave works. A transistor is product of a conductive material like silicon or germanium. They will take in electrons in the same method as a capacitor, however they don’t lose them. In RAM, the presence of electrons makes a 1, but with flash memory, an electron cost makes a zero and no charge is a 1. As a result of they don’t lose their electrons, they keep the information when they are switched off as nicely.

A transistor has two ends. The electrons can enter in via the one end, known as the supply, and they'll leave the transistor by way of the opposite end, called the drain. There is a gate at one end and electrons are saved within the transistor when the gate is closed, being read as 0. If the gate is left open, the electrons go straight by way of and the transistor is empty, being read as 1. With non-flash Memory Wave Experience, when the facility is turned off, the electrons don’t keep within the transistor. Flash drives have to work when there isn't a power source and this is finished with one thing referred to as a floating gate. A floating gate is a gate simply just like the one which retains the electrons within the transistor, but it's separated from the transistor by a thin, oxide layer. The oxide is an insulator however because it's skinny, electrons can cross by it if there is a robust sufficient present.

When the pc writes to a flash memory, it makes use of enough present that the electrons fill the transistor, pass across the insulating layer and persist with the floating gate. The computer makes use of enough current for the electrons to cross over the floating gate, however they don’t have sufficient energy to get again across, so that they keep stuck to the floating gate. They'll stay that means for years without any additional power and with out lack of memory. If you wish to erase data from the flash memory, the pc supplies an electric present to the entrance of the transistor and a negative cost to the gates. This repels the electrons on one side and attracts them on the other so that they soar across the insulating layer and depart the transistor. Flash memory drives are very useful because they will retailer the information with out needing any power, however they can’t be used indefinitely. Each time the gates are electrified, they put on a little bit. Different drives have different ratings however they are good for about 100,000 write / erase cycles before they begin to leak data. And this is what I realized at this time.