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The increasing use of e-commerce is one of the factors stimulating the development of biometric technologies which is the science of measuring and statistically analyzing biological data. There is no point in being able to book holidays, buy shares or even just check your bank balance from your PC or mobile terminal unless the whole infrastructure is secure against fraud.  As one of the world’s leading suppliers of connectivity solutions, ST is fully committed to ADSL and has just introduced a new customer-premises ADSL modem chipset aimed at both laptop and desktop computers. It is the first on the market to employ a controller-less design with USB or PCI interface, reducing cost, size and power consumption while allowing simple firmware updates to extend product lifetimes. The new chipset, known as Unicorn, is based on ST’s highly successful Ascot chipset, a full-rate 8Mbps solution of which millions have already been shipped. For the Unicorn chipset, the design has been adapted to make it suitable for use in laptops and PCs, with part of the modem functions implemented by the host processor. This eliminates the need for a dedicated control processor chip, making the chipset simpler and less expensive. At the same time, the modem software is stored on the computer’s hard disk drive, allowing simple updates to be achieved. Power consumption in active mode is just 0.7W for the chipset and below 2W for the complete modem solution, thus matching USB bus power requirements. The complete solution also fits USB power rating in stand-by mode. A Unicorn chipset consists of two components: the digital ST70137 chip and one of ST’s analog front end chips - the ST70134A chip for a PCI solution or the ST70136 chip for both PCI and USB solutions. Supplied in a compact TQFP144 package using HCMOS7 technology, the ST70137 is a controller-less ADSL DMT transceiver including both PCI and USB interfaces. Using BiCMOS5 technology, the ST70136 chip comes in a TQFP64 package. The PCI interface makes it possible to build an internal ADSL CPE modem while the USB interface suits external bus-powered ADSL modems. The Unicorn chipset offers full compatibility with full-rate and G.lite ADSL standards. In addition it is compatible with USB standards and includes plug-and-play support. Thanks to Windows 98, 2000 and ME features, the plug-and-play feature makes Unicorn ideal for easy-to-use world modems. Drivers for Linux and MacOS are also planned for the second half of year 2001. Lightening the Load When “soft modems” were first proposed, PC owners were often concerned that the load on the host processor might degrade the performance of the PC while the modem was operating but this is no longer a cause for concern. In fact, ST engineers have optimized the architecture to reduce the burden on the host processor to almost imperceptible levels. Measurements on a 400MHz Intel Celeron processor running the ADSL modem in PCI mode under Windows 2000 gave a CPU load as low as 4% with the link up and with no IP traffic.   Rising slightly above 20% at 8Mbps using PPP protocol over an ATM connection; during initialization the CPU load remained around 18%. The ST70137’s hardware features include PCI 2.2 and USB1.1 compliance. Bus-powered features include support for ADSL digital processing, direct interface to ST’s ST70136 or ST70134A analog front-ends, and Microwire interface to external serial memory. The ST70137 draws only 400mW in full operation, from +3.3V and +1.8V supplies. ST70136 features include wide transmit/receive dynamic range to reduce external filtering, and activity detection for wake-up function. The ST70136 draws only 300mW in full operation, 5mW in low power mode, and 1mW in standby from +5V and +3.3V supplies. With its low power tone detector feature, the ST70136 allows wake-up of the modem from the DSLAM side, still fitting perfectly with USB power requirements. In addition to the two chips, ST also supplies a complete reference design packaged on a CD-ROM that contains schematics, bill of materials, PCB layout file, Windows USB driver and a hardware manual. The Unicorn shipping package also includes a complete set of software tools for Windows 98, 2000 and ME including PC software for modem control and communications protocols. Full ATM support is assured by the inclusion of drivers for PCI Interface, USB with ADSL modem control, and ATM devices. Configuration and diagnostic tools are also provided, while built and tested evaluation boards for the reference design are also available. Most Challenge readers, will not need convincing that the Internet is a powerful and increasingly vital resource - provided, that is, that your office has a high-speed connection. Many home users, annoyed by long download times, are not yet convinced. With the new chipset, ST is again playing a key role in making the Internet a more useful and enjoyable resource.  |
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