U disk, the full name is "USB flash disk", and its English name is "USB flash disk". It is a micro high-capacity mobile storage product with a USB interface that does not require a physical drive. It can be connected to the computer through the USB interface to achieve plug-and-play. The name USB flash drive originally came from a new type of storage device produced by Netac, called "USB flash drive", which uses a USB interface to connect. After the USB interface is connected to the computer host, the data on the USB flash drive can be exchanged with the computer. Since Netac has registered patents for equipment with similar technology produced later, it can no longer be called "U disk" and is renamed the homophonic "U disk". Later, the name U disk became widely known because it was simple and easy to remember, and until now, the two have been used in common, and no distinction is made between them. It is one of the mobile storage devices.
Invention History
From 1998 to 2000, many companies claimed to be the first to invent the USB flash drive. Including China's Netac Technology, Israel's M-Systems, and Singapore's Trek. But it was China Netac that actually obtained the basic invention patent for USB flash drives. In July 2002, Netac's "fast electronic storage method and device for data processing systems" (Patent No.: ZL 99 1 17225.6) was officially authorized by the State Intellectual Property Office. This patent fills the gap in invention patents in the field of computer storage in China in the past 20 years. The acquisition of this patent caused great shock in the entire storage industry. Israel's M-Systems immediately filed an invalidation review with the State Intellectual Property Office of China, which once became a patent dispute that shocked both China and foreign countries in the global flash memory field. However, on December 7, 2004, Netac received the flash disk basic invention patent officially authorized by the US National Patent Office, US Patent No. US6829672. The acquisition of this patent finally ended the competition. . China Netac is the world's first inventor of USB flash drives. On February 10, 2006, U.S. time, Netac entrusted American lawyer Morgan Lewis to submit a complaint to the Federal Court for the Eastern District of Texas, accusing the U.S. company PNY of infringing Netac's U.S. patent (U.S. Patent No. US6829672). In February 2008, Netac and PNY reached an out-of-court settlement. Netac signed a patent licensing agreement with PNY, and PNY paid a patent licensing fee of US$10 million to Netac. This is the first time that a Chinese company has received huge patent licensing fees in the United States. It also further proves that Netac is the global inventor of USB flash drives.
Today’s flash drives all support the USB2.0 standard; however, due to technical limitations of NAND flash memory, their read and write speeds are currently unable to reach the maximum transmission speed of 480Mbit/s supported by the standard. The fastest flash drives currently use dual-channel controllers, but they are still far behind the current era of hard drives or the maximum transfer rate that USB2.0 can provide. The current highest transfer rate is about 20-40MB/s, while the general file transfer speed is about 10MB/s. Older 12Mbit/s devices have a maximum transfer rate of only about 1MB/s. Among them, the leaders in the industry include Shenzhen Netac Company, M-Systems Company, and Singapore Trek Company.
U disk to expand the system cache
Under the Microsoft Windows Vista operating system, the ReadyBoost function allows you to improve system performance by simply inserting a USB flash drive and making slight configurations. And use USB 2.0 flash memory to accelerate the performance of Vista PC, using the USB memory space as system memory.
Of course, the prerequisite for using the ReadyBoost function is that the USB flash drive must meet certain performance and capacity requirements: at least 2.5MB/s transmission, 4K random read speed, 1.75MB/s transmission, 512K Random write speed; 64MB to 8GB free space; total capacity at least 256MB. These are just the basic parameters officially given by Microsoft. If you want to perfectly experience ReadyBoost performance, you still need higher-performance flash memory for support.