USB flash drives have become extremely popular as giveaways and incentives in recent years. They are used on a daily basis for storing and transporting data but like so many other computer-related items it is sometimes a mystery how they actually work!

There are typically three parts to a flash drive:

• Male type-A USB connector – provides an interface to the host computer.
• USB mass storage controller – implements the USB host controller. The controller contains a small micro-controller with a small amount of on-chip ROM and RAM.
• NAND flash memory chip – stores data. NAND flash is typically also used in digital cameras.

A typical flash memory device has a housing including a small printed circuit board (PCB), and an integral connector for connecting to a USB port on a computer. The USB flash drive is connected to a computer either by direct connection or via a USB hub. When plugged into a USB port, the computer’s operating system recognizes the flash memory device as a removable drive and allows data to be retrieved from and added to the flash memory drive. Most flash drives require no other external power source or battery power source as they become active when connected with a computer. More >