TI Extends Leadership in Data Transmission with New Technologies
An Overview of
TI's Data Transmission Product Line
Thirty years ago, before anyone had heard of the Internet and computers were anything but personal, Texas Instruments (TI) was already a leader in data transmission. During the intervening years, pioneering research and development in low voltage differential signaling (LVDS), IEEE 1394 FireWire™, universal serial bus (USB) and other technologies has assured the company will continue to provide break-through products that will be the backbone of tomorrow's global information infrastructure. TI's Mixed Signal Products group has the necessary expertise in both analog and digital technologies to push the limits of speed, transmission distance, low power and reduced cost.
Pushing the Speed Limits and Decreasing Power with LVDS
As the performance of computer processors and memories accelerates, it is imperative to move data into and out of (I/O) computer systems with the utmost speed, and with low power and low electromagnetic interference (EMI). Otherwise, bottlenecks develop and the system performance is limited by the I/O.
A new transmission technology known as LVDS was originally developed to meet the industry's needs for high speed and low power. It was initially used to move data in and out of high-speed memory. However, the speed and low power features of LVDS were soon found to be desirable for other applications such as linking a portable computer's graphic subsystem with the system's flat panel display screen. It has also been used for other general-purpose data interchanges. More recently, LVDS has been adapted to the small computer system interface (SCSI) bus, which is used extensively in computer I/O subsystems.
When used with a portable computer's graphics subsystem, TI's trademark for LVDS technology is FlatLink™. When LVDS technology is used in this application, it provides 234.5 megabytes (MB) per second link over five 100-Ohm cables. TI has released an extensive family of FlatLink transmitters and receivers for use in portable computers.
When used in a computer's SCSI I/O subsystem, LVDS technology is designated LVD-SCSI and is one of the signaling options for a Fast-40 SCSI bus. Fast-40 SCSI has a data rate of 40 million transfers per second over a distance of up to 12 meters. In contrast, older, single-ended SCSI implementations support 20 million data transfers per second, but only over a distance of 1.5 meters. TI has announced a multi-channel LVD-SCSI transceiver that is well suited for use in SCSI subsystems, but can also be used in many other multiplexed parallel buses.
General purpose LVDS drivers, receivers and transceivers cover a wide range of applications for point-to-point and multidrop baseband data transmission over controlled impedance media of approximately 100 Ohms. The transmission media may be printed circuit board traces, backplanes or cables. To assure interchangeability for these general uses, LVDS was standardized by ANSI in the form of TIA/EIA-644. TI has an extensive roadmap of general-purpose drivers, receivers and transceivers that meet or exceed the TIA/EIA-644 standard requirements.
IEEE 1394 and USB: Next Generation PC I/O
A glance at the back of most personal computers reveals a confusing array of connectors and different types of cables leading to printers, keyboards, mice and other peripheral devices. TI has taken an active role in two initiatives, IEEE 1394 FireWire and USB, which will simplify this situation and provide high-speed data transmission speeds for demanding PC applications.
When the 1394 specification for a high-speed serial bus for backplane and cable-connected applications was first being implemented in 1994, TI's Mixed Signal Products group introduced the industry's only fully compliant 1394 chipset comprised of physical layer and link layer interfaces. The speeds of TI's 1394 solutions have increased over the years from 100 to 200 and most recently to 400 megabits per second (Mbps). Meanwhile functionality has expanded to include support for user-configurable first in first out (FIFO) memory, as many as five direct memory access channels, 8- or 16-bit zoom video and other features.
While 1394 is well suited to many PC applications, some peripheral devices like keyboards and mice simply don't need the high-speed capabilities of 1394. For these medium- to low-speed devices, USB provides a simple solution with an easy-to-use connector. TI has developed the industry's most innovative product line of USB components and, in fact, is the only semiconductor supplier to provide all of the integrated circuits needed to develop a USB hub. These devices include hub controllers with multiple ports, low drop-out voltage regulators, line transient suppressors and power distribution switches.
Moving Data on the PCIBus
Data transmission speed and efficiency is also critical within the PC itself. With today's high-speed microprocessors, moving data along the PCIBus can be the limiting factor in overall PC performance. PCIBus controllers manage that data traffic flow.
Early involvement in standard setting activities and close working relationships with strategic customers have led to the development of TI's broad and deep PCIBus product line with many ground-breaking firsts in the industry. TI's CardBus controllers address every segment of the market; from handheld applications with single-socket CardBus requirements to high-performance multimedia portable computers needing dual-socketed CardBus controllers. Between either end of the market, TI's various PCIBus controllers have been targeted to provide just those features needed to satisfy cost-conscious consumers.
In 1995, during the nascent stages of the CardBus market, TI introduced the first CardBus controller for the PCIBus. Moreover, this CardBus controller was the first to receive a Windows 95® logo; signifying TI's device passed the Windows Hardware Quality Lab requirements. With a parallel pipelined FIFO architecture, TI's CardBus controllers were the first in the industry to achieve the PCIBus theoretical maximum data transfer rate of 132 MBps.
In keeping with the pioneering work it has done on industry standards, TI has been first to market with PC Card and CardBus controllers that support critical specifications like the PCI Power Management, ACPI and Device Class Power Management.
Supporting Current Standards
Along with TI's efforts to extend the data transmission capabilities of new technologies like LVDS and IEEE 1394, the company continues to improve currently implemented transmission specifications such as RS-232, RS-422, RS-485, GeoPort®, IrDA and others. In addition, the company has a varied family of universal asynchronous receiver/transmitters (UARTs) that are used extensively in personal computers.
TI is a major supplier to the personal computer industry where the RS-232 communication standard has been used for years to interface peripheral equipment to PCs. The company's RS-232 product family continues to extend the capabilities of the RS-232 standard with higher speeds, reduced EMI and a wider selection of driver/receiver combinations. Because of the wide range of RS-232 transceivers offered by TI, a solution is available for practically any application no matter what the price/performance goal.
Other standards, such as RS-485 and RS-422, are differential technologies and are used in a broad selection of general-purpose applications, including industrial control, telecommunications, point-of-sale terminals, alarm systems and other environments that are high in electrical interference. Transmission speeds up to 30 MB per second over distances up to several kilometers are supported. TI's RS-422 and RS-485 product families include many combinations of drivers, receivers and transceivers.
Tools and Support
In addition to its advanced technology, TI is also providing the tools and support to enable innovative designs in data transmission.
For example, in IEEE 1394, TI offers hardware design kits, software development systems and software for both ends of the connection -- both the PC and the peripheral end-equipment. This support allows end-equipment designers to quickly and effectively incorporate 1394 connections into their next generation designs.
In PCIBus, TI has created the most extensive compatibility-testing lab in the industry. It currently includes PC Card and CardBus modules from more than 80 manufacturers, and the modules tested cover as many as 25 different functions including fax/modem modules, memory cards, wireless communications, data acquisition, video capture, hard drives, network interface cards and others. This type of testing gives notebook computer manufacturers some assurance their systems will support the wide variety of PC Cards now available in the market.
Positioned for Leadership
Aside from pushing the envelope in data transmission technology and support, other factors have contributed to TI's success. TI's stringent quality assurance programs and its global manufacturing capacity help its customers bring their products to market within shrinking time-to-market windows. Customers can be assured of a reliable and responsive supply of components.
Finally, TI's expertise in both high-speed analog and digital technologies and its 30 years of experience developing leading-edge products demonstrate the group's commitment to push the limits of data transmission technology now and in the future.
More information on TI's data transmission solutions is available on the World Wide Web at 
http://www.ti.com/sc/docs/msp/datatran/default.htm.
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