What is the principle of storing data on U disk?

The principle of data storage by U disk is that the computer converts the binary digital signal into a composite binary digital signal (adding instructions such as allocation, check and stack) and reads it to the USB chip adapter interface, and then stores the binary data to the corresponding address allocated to the NAND flash memory chip through the chip processing signal, thus realizing data storage.

The control principle of data memory is that the voltage of gate transistor is controlled by voltage, and the junction capacitance of gate transistor can store voltage for a long time, which is why USB can store data after power failure.

Extended data:

Flash memory, as its name implies, deletes data for initialization before writing. Specifically, electrons are extracted from all floating gates. Some data will return to "1". Write only when the data is 0, and do nothing when the data is 1 When writing 0, a high voltage is applied to the gate electrode and the drain electrode, which increases the electron energy conducted between the source electrode and the drain electrode.

In this way, electrons will break through the oxide film insulator and enter the floating gate. When reading data, a certain voltage is applied to the gate electrode, the current is 1, and the current is 0 if it is small. When there are no electrons in the floating gate (data is 1), when a voltage is applied to the gate electrode, a voltage is applied to the drain, and a current will be generated between the source and the drain due to the movement of a large number of electrons.

But when there are electrons in the floating gate (data is 0), the electrons conducted in the channel will decrease. Because the voltage applied to the gate electrode is absorbed by the floating gate electrons, it is difficult to affect the channel.

Zhongguancun Online-Summer Lecture Hall: How to Recover Misdeleted Data from Hard Disk