“Pen drive“ is a portable USB flash memory device that can be used to quickly transfer audio,video and data files from the hard drive of one computer to another. It uses a tiny PCB (Printed Circuit Board) to store large amounts of data and its data storage is based on EEPROM technology.
What’s a flash memory?
Flash memory is a type of EEPROM memory. Its a memory chip that holds stored information without requiring any power source.
What’s an EEPROM?
EEPROM stands for Electrically Erasable Programmable Read Only Memory. Its a form of non-volatile memory that can be altered electrically.
USB flash drive contains a small PCB with the flash memory chip, or chips mounted on it and a male type-A USB connector attached at the one end. The PCB contains a microprocessor that acts as a USB mass storage controller, which allows the pc to access the flash memory in a simple linear manner.
The controller handles the block mode access that is inherent with NAND flash RAM and performs functions such as wear- leveling, to make sure all the blocks of the flash RAM chip get equal usage. This is important because there is a limit on the no: of times that NAND can be written to and if data copied to it always used the same blocks first ,those blocks would wear out faster , rendering the whole chip useless before some of the blocks have been used much, if at all.
The PCB will also have an oscillator, providing a clock signal to control data transfer operations, and usually an LED, sometimes two, which can show the activity status of the flash drives. The LED act as a warning that device is in use as unplugging it without unmounting can damage the drive beyond repair.