Tech Primer

USB Flash

What is a USB Flash Drive and what are its applications?

A USB Flash Drive is a compact memory drive that acts like a portable hard drive, letting you store and transport files and applications. It holds a fairly large amount of information and is yet small enough—about the size of a pack of gum. Plugging your USB Flash Drive into the USB port of a computer lets you transfer files to and from the drive using Windows Explorer.

Will the USB Flash Drive work with any computer? How much does it cost and what’s the maximum capacity it can accommodate?

USB Flash Drives inter-operate with PCs (and Macs). Typically, USB Flash Drives use the mass storage class drivers that are incorporated in Windows ME, 2000 and XP, Mac OS 9 and OS X, as well as Linux 2.4.6 or later. Some manufacturers offer drivers for Windows 98 SE or NT too. Apple offers a mass storage class driver update for Mac OS 8.6. These are available in capacities ranging from 128 MB to 2 GB. A 128 MB USB Flash Drive can cost Rs 1,000 while a 1 GB drive comes at about Rs 4,000.

Is a USB Flash Drive better than CD-R or DVD-R or an external hard drive for that matter?

While you can read a CD-R on almost any computer with a CD-ROM drive, you cannot write to it more than once. Even with a CD-RW rewritable disk you need a CD writer to write to it. Moreover, the process of uploading files from your computer to a USB Flash Drive is much faster and simpler than burning a CD or DVD. USB Flash Drives act like portable hard drives to which you can add and delete files as many times as you like. With CD-Rs and DVD-Rs, you can only add data once, and you cannot remove data after it’s burned onto the disk. In comparison to external hard drives, USB Flash Drives are far smaller and they are a lot more reliable than external hard drives. They are easier to connect to your computer than external hard drives.

Who needs a USB Flash Drive?

If you frequently need to transfer data from your work PC to your home computer, or you just want to keep a personal backup of your most precious computer data, a USB Flash Drive is for you. With USB Flash Drives you can transport a PowerPoint file to your client’s office to make a presentation, work on documents from home and then bring them back with you to work in the morning, bring thousands of digital photos across the country to share with your relatives—and do much more.

Are USB Flash Drives susceptible to corruption from airport security scanners?

In general, USB Flash Drives should be airport security safe. However, it depends on the non-volatile memory used within the device. Please check with your manufacturer for detailed specifications.

Where can I find a driver to download so I can use a USB Flash Drive on my older computer?

Most USB Flash Drives use mass storage class drivers. These are included in Windows ME, 2000 and XP. In order to operate under Windows 98 SE, a USB Flash Drive typically requires a driver that you can usually obtain from its manufacturer through their customer service support number or Web site.

What is the general architecture of a USB Flash Drive?

A USB Flash Drive consists of a controller with a USB interface and a non-volatile memory interface that is connected to one or multiple non-volatile memories (lower levels or higher levels of integration are possible). Hi-speed UFDs (USB Flash Disks) use a crystal for external clock generation, and an LED is typically used as an optical activity indicator, possibly a write protect switch to control write access and some other components that are used for the remaining circuitry. Beyond this configuration, other components might be integrated depending on the functionality of a drive such as MP3 player, fingerprint sensor, etc.

Are USB Flash Drives intended to be hot-pluggable (that is, you can plug one in, or remove it, with the computer already on)?

The USB interface standard was created with the hot-pluggable feature in mind. Any USB device can be inserted or extracted while the computer is on. This applies to USB Flash Drives as well, which, in general, use mass storage class drivers. Therefore any system that supports mass storage class drivers should be able to access the content from the USB Flash Drive—including music files.

Are there many manufacturers of these products?

USB Flash Drives are manufactured and sold by a number of different companies, including IBM, Lexar Media, Kingston Technologies, SimpleTech, PNY Technologies, Viking InterWorks, Sony, Iomega and Transcend. Most of these brands are available in India.

For more information visit www.usbflashdrive.org/usbfd_faq.html