How does the USB flash drive work?
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USB flash drives or USB flash drives are devicesfor storing, recording and reading information. Thanks to them, we can carry huge amounts of data in our pocket: photo albums, music concerts, price lists, maps, presentations, etc. But how does this become possible? Let's talk in this article about how the flash drive works.
How does the USB flash drive work?
The most simple flash drive is designed for a minimum of 10,000cycles of overwriting. But the best specimens can withstand 100,000 cycles. If you do not overwrite the information several times a day, this resource could be enough for an unlimited time. However, usually data is stored for no more than 10 years. As a rule, during this time people have time to replace the drive several times with a more modern device.
And nevertheless, sometimes it happens that the flash cardsuddenly fails: when connected, the computer "does not recognize" it, informing that it is an "unknown device". To understand why a flash drive does not work, you need at least in general to represent its device.
Inside the small flash drive there are several blocks:
- microcontroller;
- chip (chip) of flash memory;
- source of clock frequency - quartz resonator;
- Light-emitting diode;
- write-protect switch.
The main part is the memory matrix. It consists of many cells in which information is recorded. One cell is 1 bit of information. The computer uses binary logic: it only operates on zeros and ones. There is voltage in the cell - unit, no voltage - zero. In order to write down one character - a letter, a number, a space, etc. - need 8 bits or 8 cells. 8 bits are called bytes. In each flash drive can store millions of bytes of information.
The main advantage of the memory matrix is that the data is not lost when there is no supply voltage, i.e. it is nonvolatile.
Controls the work of memory cells controller, thisdrive control unit. The controller connects the current to all cells, checks where 0 is recorded, and where 1. The signal from the computer is fed to it via the connector.
In accordance with this request signal, the blockcontrol refers exactly to the cells that are specified in the request, and allows the data recorded in these cells to enter the computer. Alternatively, the controller reads data from the computer and sends them to the selected cells.
For the normal operation of a flash drive, a clock frequency is required, which is generated by a quartz resonator. It is he who sets the speed of the flash drive.
What to do to make the flash drive work without interruption
Never remove the USB flash drive from the workingcomputer. Pre-disable it. In these cases, the computer writes that the memory device can be deleted. This means that a shutdown signal has been sent from the computer to the controller, and the corresponding service information has been recorded in the control unit.
If you pull out the USB flash drive without turning it off, incontroller, the service information may fail, and then it will no longer be able to connect to the reader. The same can happen when sudden voltage drops occur.
The controller is the most vulnerable part of the flash drive. The quality memory matrix and quartz oscillator almost never fail. To destroy them, you must either break the USB-device, or submit a very high voltage. But the connector can be crippled if you treat it with carelessness.
