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leading edge WISH VERSUS REALITY “Right now, with deep- By Bill Schweber he AD9884 from Analog Devices makes T enabling millions of signals with flat-panel displays—a task that transistors on a chip, involves considerable mixed-signal process- the gap may still be ing and support functions. The device incorporates a trio of high-speed, wideband, 8-bit A/D converters plus an input buffer, a pixel clock, and related circuits in a 128-lead PQFP device. The IC has a 140M-sample/sec encoding rate with a 500-MHz full-power bandwidth, commensurate with displays of 128021024-pixel resolution using a 75Hz refresh rate. The PLL within the AD9884 develops a pixel clock over a 20- to 140MHz range with less than 500-psec p-p jitter from a what the industry would like to build using intellectual-property-based design methodologies and what can be built.” —Robin Saxby, CEO of ARM it easier to use your analog RGB video horizontal sync input of 30 to 90 kHz. You can disable the PLL to use an external clock signal if you prefer. An internal 1.25V reference, programmable gain, and clamp circuitry further reduce the need to provide peripheral functions. You program this $25 (10,000) CMOS IC via a two-wire serial bus, and you can also get a slower, 100M-sample/sec version for $20. 3Analog Devices Inc, Norwood, MA. 1-781937-1428, fax 1-781-8214273, www.analog.com. 3Circle No. 393 Simplify the analog-to-digital hassles between RGB video outputs and LCD panels with the AD9884 triple digitizer, which includes clock-generating PLL. Flash drive stores 160 Mbytes in 1.3-in. package Flash-disk provider M-Systems has added support for an even smaller form factor to its ATA-based product family. The Model IDE 1.3-in. products matches the 1.3in. form factor that Hewlett-Packard (www.hp.com) pioneered and abandoned with its Kittyhawk magnetic disk drive. Available in capacities of 4 to 160 Mbytes, the drives target handheld and ultraportable systems. You can specify the products in standard (0 to 70 C), enhanced (225 to +75 C), and extended (240 to +85 C) versions. A standard 160-Mbyte product sells for $440 (OEM), and the company offers the same capacity in a 1.8-in. package for $427.—by Maury Wright 3M-Systems, Newark, CA. 1-510-413-5950, www.m-sys.com.3Circle No. 394 www.ednmag.com Edited by Fran Granville Triple ADC with on-chip PLL carries analog RGB over to flat-panel world submicron technology widening between What’s hot in the design community R&D ON THE RISE Paced by the fast-growing hightech industry, R&D spending in the private sector is expected to increase to $157.1 billion this year from about $143.1 billion in 1998, according to an annual survey by contract-research company Battelle Memorial Institute and R&D magazine. —James P Miller, The Wall Street Journal, Thursday, Dec 31, 1998. January 21, 1999 | edn 13 leading edge Analog front end for ADSL extends linearity and local-loop length hereas many asymmetrical digital-sub- W scriber-line (ADSL) front ends have speci- fications that suit loops 12,000 to 16,000 ft from the central office, this distance covers only 60% of US residents. In contrast, Datapath’s DSP8000 analog front end offers high linearity and low noise, providing an 18,000-ft loop covering more than 95% of residents. The DSP8000 (for remote-termi- nal end users) and similar DSP8001 (for central-office sites) sport 14-bit linearity from 4.416M-sample/sec A/D and D/A converters, plus a receiving noise floor of 2150 dBm/Hz above 300 kHz. The 9 8 7 14 BITS, 2150 dBm/Hz 11 BITS, 2145 dBm/Hz 6 5 DATA RATE (MBPS) 10 BITS, 2140 dBm/Hz 4 8 BITS, 3 2140 dBm/Hz 2 1 0 2000 4000 6000 8000 10,000 12,000 14,000 16,000 18,000 LOOP DISTANCE (FT) Higher linearity and receiver noise floor have a major effect on the data rate and distance you can achieve in ADSL implementations. DILBERT By Scott Adams ICs comply with the ADSL T1E1.413 standard, yielding 8 Mbps downstream and 800 kbps upstream on short lines and 1.5 Mbps bidirectionally on longer loops. Each 128-pin PQFP IC requires four external precision resistors plus a few bypass/decoupling capacitors, as well as standard plain-old-telephone-system “reject” filtering and high-voltage line drivers and receivers. Within the 5V devices are fourth-order lowpass filters for the transmitting and receiving paths with 5% cutoff-frequency accuracy, programmable attenuation and gain for each path, and a 12-bit DAC for the voltage-controlled crystal oscillator. You configure the analog front ends via a four-wire serial port; power consumption is 675 mW in frequency-division mode and 825 mW with full echo-cancellation operation enabled. The DSP8000 and DSP8001 cost $22.50 (100) each.—by Bill Schweber 3Datapath Systems Inc, Los Gatos, CA. 1-408-366-1766, fax 1-408-366-1955, www. datapathsystems.com. 3Circle No. 395 FAST FPGAs FOCUS ON PCI DynaChip has made several tweaks to its year-old DL6000 architecture, and the end result is the DY6000 family (see “Budding FPGAs beat last year’s crop,” EDN, March 26, 1998, pg 18). Each logic block now contains an 8-to-1 multiplexer; 16input AND-OR logic; arithmetic logic that can, for example, implement a 2-bit adder or seveninput XOR function; and dual flip-flops. You can now drive each synchronous port of the 32-bit dual-port RAM in each logic block with a different clock as fast as 125 MHz. Speaking of megahertz, the two on-chip analog PLLs, which operate as fast as 205 MHz, can not only divide and multiply an input clock, but also enable you to insert programmable latency from 24 to +2 nsec. DynaChip made many of these enhancements with PCI and other highperformance interfaces in mind. The company claims that its 64bit firm core runs zero-wait-state PCI as fast as 66 MHz, consuming one-third of the largest device in the DY6000 family and leaving approximately 36,000 gates for other functions. The 55,000-gate DY6055, now in production, offers 1600 logic blocks; 51,200 bits of RAM; 3840 flip-flops, including I/O registers; and 320 I/O signals. It costs $174 (1000) in 240-pin QFPs or $229 (1000) in 432bump BGAs. The DY6009, DY6020, and DY6035 are available for sampling. The company’s DynaTool back-end placeand-route software also supports the DY6000 family. —by Brian Dipert 3DynaChip Corp, Sunnyvale, CA. 1-408-481-3100, fax 1-408481-3136, www.dyna.com. 3Circle No. 396 FACTOID3International Data Corp reported in December that more than 500,000 copies of Linux shipped during the year, more than three times the number shipped in 1997, making it the fastest-growing server operating system. 14 edn | January 21, 1999 www.ednmag.com leading edge RISE-TIME ACCELERATOR GETS YOUR BUS MOVING IN THE FAST LANE To speed the rise time and thus improve performance of your System Management Bus (SMBus), the LTC1694 from Linear Technology provides dual active pullups that dynamically boost transition currents to 2.2 mA on data and clock lines. This approach improves data integrity, timing margins, and system robustness, despite long bus traces or the connection of additional peripherals. The five-pin SOT23 device operates from nominal 5 or 3.3V supplies and yields 1-msec rise time with a 200-pF bus capacitance. The accelerator costs $1.15 (1000). —by Bill Schweber 3Linear Technology Corp, Milpitas, CA. 1-408-432-1900, fax 1-408-434-6441, www. linear-tech.com. 3Circle No. 397 Power-distribution IC switches divide loads and conquer battery limits y shutting down blocks of circuitry, you ex- B tend battery life, reduce thermal loads, and isolate failures in your designs. Members of three power-distribution switch families from Texas In- struments let you segment and then enable or disable your system’s loads, including hot-swap and Universal Serial Bus applications. The families—TPS201XA, TPS202X, and TPS203X—offer a selection of multiple current ratings, positive- or negative-enable logic levels, and optional overcurrent indication. All switches have a maximum 50mV on-resistance and 45msec overcurrent-response time. The eight-pin SOIC/ DIP and 14-pin TSSOP switches handle continuous currents from 0.3 to 3A, depending on model, and cost $1.01 to $1.11 (1000). —by Bill Schweber 3Texas Instruments Inc, Dallas, TX. 1-800-477-8924, www. ti.com.3Circle No. 398 Power switches in the TPS201X, TPS202X, and TPS203X families let you segment and then control power-distribution subsystems. DIGITALLY DIM YOUR LCD BACKLIGHT OVER 100-TO-1 RANGE Cold-cathode-fluorescent lamps (CCFLs) find extensive use in backlighting LCD monitors but require complex drive circuitry. Avoiding that complexity, the LX1686 from Linfinity Microelectronics implements a new architecture for the drive circuitry. The architecture eliminates some external passive reactance components, allows you to use a smaller step-up transformer, and yields a wide brightness-adjustment ratio. The 24-pin IC includes dual 100-mA drive outputs that can connect directly to FETs or bipolar transistors. Within the IC, the fixed-frequency PWM control circuit has two feedback loops—one to regulate lamp By dynamically boosting SMBus current during signal transitions, the LTC1694 significantly improves system timing integrity and reduces hard-totrace soft timing errors. current and the other to regulate open-circuit, or “strike,” voltage amplitude. The LX1686 provides and automatically monitors the special start-up voltage sequence that CCFLs require. The device also controls both its output current burst to minimize overshoot, which shortens lamp life, and its output pulse jitter, which can cause flicker from beat frequencies. The IC costs $3.30 (1000).—by Bill Schweber 3Linfinity Microelectronics Inc, Garden Grove, CA. 1-714-372-8335, fax 1-714-372-3566, www.linfinity.com. 3Circle No. 399 FACTOID3Linux scored highest of nine competitors in overall satisfaction in a recent survey conducted by Datapro, posting a score a bit lower than 3.8 on a zero-to-five scale, in which five means “completely satisfied.” In overall product quality, Linux fared worse, placing seventh among the nine with a score of about 3.8. 16 edn | January 21, 1999 www.ednmag.com leading edge LOW-COST TOOLS EASE mC-BASED SYSTEM DESIGN The PSDsoft tool suite from WSI makes life a little easier for designers of support chips for mCs. WSI developed the tools for use with its PSD chips, which integrate programmable logic, in- system-programmable (ISP) flash, EEPROM or EPROM, SRAM, I/O, and programmable functions on one chip. The $89 Windows-based PSDsoft simplifies adding external logic and memory to mC-based systems. PSDsoft supports HDL-based logic design, simulation of PSD-chip CPLD functions, mCinterface configuration, memory mapping, and programmable-function configuration on PSD chips. It also automatically generates C code for implementing ISP functions. The tool suite comes with templates for bus-interface configuration for many mCs, including the 68HC11, 8031, 80196, and 3150. PSD chips contain all required logic for the interface, which means you need no additional chips. Device-configuration options include bus width, multiplexed or nonmultiplexed operation, and mC bus-control settings for most popular 8- and 16-bit mC buses. PSDabel, WSI’s version of the Abel PLD programming language, lets you do your PSD logic design using Boolean equations, truth tables, and state diagrams. An optimizer automatically reduces logic by eliminating redundancy and maximizing resources. When you finish configuring your device, logic design, and mC firmware, PSDsoft helps you merge these results and map them to a target PSD. Finally, PSDsoft generates PSD-macrocell-usage reports along with a pinout diagram for next-level board design.—by Jim Lipman 3WSI, Fremont, CA. 1-510-6565400, fax 1-510-657-5916, www. wsipsd.com.3Circle No. 400 18 edn | January 21, 1999 Bigger+smaller MOSFET switches cut parts and design overkill n cost-sensitive designs—and which rare ones I these days aren’t?—any overdesign or the need for small external components can add expense to your bill of materials. Recognizing this fact, two MOSFET vendors offer entries with functions tailored to an application’s precise needs. From Vishay Siliconix, the PWM-optimized Si4824DY IC has asymmetric, dual, 30V n-channel MOSFETs in a single SO-8 package. One MOSET is a 17.5-mV device, and the other is a 40-mV device; together, the MOSFETs work well in synchronous-buck dc/dc-converter designs with optimal on-resistances for both the switching and the synchronous portions of the design. Gate charges for the MOSFETs are just 12 and 31 nC, adding to the efficiency of the 63-cent (100,000) devices. Along the same application-optimized concept, the FDC6325L from Fairchild Semiconductor combines a low-on-resistance p-channel MOSFET with a smaller nchannel MOSFET driver in a six-pin SOT package. The company designed this integrated load switch for highside power switching. It lets you drive the p-channel device directly from low-voltage logic circuits, eliminating the need for an external levelshifting transistor. Operating from battery voltages of 2.5 to 8V, the FDC6325L has 130 and 180 mV maximum onresistance at 5 and 2.5V, respectively, and can switch continuous loads as high as 1.8A (5A pk). A similar device, the FDC6326L, handles 3 to 20V loads but with on-re- sistance values of 125 mV at 12V and 200 mV at 5V. The devices cost 49 cents (1000) each.—by Bill Schweber 3Vishay Siliconix Inc, Santa Clara, CA. 1-408-567-8220, fax 1-408-567-8995, www. siliconix.com. 3Circle No. 401 3Fairchild Semiconductor Corp, Sunnyvale, CA. 1-408822-2000, fax 1-972-9108039, www.fairchildsemi. com.3Circle No. 402 The Vishay Siliconix Si4824DY puts a larger and smaller on-resistance pair of MOSFETs in one package for use in synchronous-buck dc/dc converters. The Fairchild Semiconductor FDC6325L and FDC6326L each incorporate a larger p-channel device with a smaller n-channel device as a driver, so you can drive the MOSFETs without external level-shifting circuitry. www.ednmag.com leading edge NICKEL-ELECTRODE MLCCs BOOST CAPACITANCE, LOWER IMPEDANCE A new line of multilayer ceramic chip capacitors (MLCCs) from Taiyo Yuden uses nickel electrodes to lower cost (versus units using palladium or silverpalladium). The chip capacitors are available in values of 0.1 to 100 mF in Y5V, X5R, and X7R formulations. The company claims that the low-impedance, nickelbased capacitors used in bypass or smoothing circuits outperform tantalum and aluminumelectrolytic units with capacitance values two to 20 times Nickel replaces precious metal in Taiyo Yuden’s multilayer capacitors; the result is low impedance and high volumetric efficiency. higher. Their advantages over tantalum and aluminum capacitors include lower effective series resistance, lower heat generation, no polarity, and smaller sizes. Case sizes range from 120.520.5 mm to 3.22 1.621.6 mm. Prices range from 1 cent to $1.50 (OEM). —by Bill Travis 3Taiyo Yuden USA, San Jose, CA. 1-408-573-4150, ext 16, fax 1-408-573-4159, www.t-yuden. com.3Circle No. 403 Voodoo offers new features for believers, trade-offs for skeptics he Voodoo3 architecture from 3Dfx Interactive T continues the single-chip-integration trend the company began with its Voodoo Banshee (see “Hot summer delivers scorching graphics,” EDN, Oct 22, 1998, pg 16). The Voodoo3 family, currently comprising two devices, offers substantial functional and performance improvements over Voodoo2-based chips. However, 3Dfx made some surprising feature-set tradeoffs to achieve these goals. Voodoo3 contains both 2and 3-D graphics cores, plus hardware assistance for digital-versatile-disk decoding. Unlike Voodoo Banshee, the 3-D core offers the same dual texture-rendering pipelines and single-cycle, single-pass multitexturing capability as the 3-D-only Voodoo2. The company has also cranked up the performance, claiming more than 7 million-triangle/sec rendering for the highend, $45 (10,000) Voodoo3300. The device also offers a 366-megatexel/sec fill rate, a 350-MHz RAMDAC capable of 204821536-pixel resolution at 75-Hz refresh, and a 183-MHz core operating frequency. These capabilities exceed those of the current 3-D performance leader: two Voodoo2 chips operating in a scan-line-interleave mode. Corresponding specifications for the $35 (10,000) Voodoo3-200 include 4 million-triangle/sec rendering, a 250-megatexel/sec fill rate, a 300-MHz RAMDAC capable of 204821536-pixel resolu- tion at 65-Hz refresh, and a 125-MHz core operating frequency. Both chips include a 22 Advanced Graphics Port (AGP) sideband interface (with 42 AGP support planned for this year), a video-module-interface port, and direct connection to 3Dfx’s optional LCDfx flatpanel-display-driver chip. According to 3Dfx, both chips are available for sampling and will enter volume production in the second quarter. So what’s not to like about Voodoo3? First, the chips support only a maximum 16Mbyte frame-buffer size, a curious limitation in this era of cheap DRAM and constantly growing game texture-map sizes. The company based Voodoo3 on its Voodoo2 3-D core (which itself is a minor derivative of the original Voodoo architecture). This decision undoubtedly let 3Dfx quickly get Voodoo3 to market, but it also means that the chips don’t output 24-bit color and support only 16-bit Zbuffer precision. Both factors reduce image quality, and, although these trade-offs may make the chips faster, why do the devices need to render new frames at rates that far exceed most viewers’ ability to perceive them? Although image quality is perhaps a secondary consideration in today’s shoot-’em-up games, it will become much more important as 3-D expands into other PC applications. —by Brian Dipert 33Dfx Interactive Inc, San Jose, CA. 1-408-935-4400, fax 1-408-262-8874, www.3dfx. com.3Circle No. 404 Higher integration and faster clock rates push Voodoo3 2- and 3-D performance to new heights, but image quality needs similar attention. FACTOID3 Working with the nonprofit Community Foundation and local and state governments, the Silicon Valley Manufacturing Group plans to raise $20 million in two years for its Housing Trust Fund to make housing in the Valley more affordable to low-income workers. 20 edn | January 21, 1999 www.ednmag.com leading edge FLASH! FOUNDRY MIGRATES LOGIC/MEMORY PROCESS TO 0.35 mm Taiwan Semiconductor Manufacturing Co (TSMC) has developed a process for integrating logic and flash memory at 0.35 mm. The merged process, EmbFlash, combines logic with a split-gate flash/EEPROM. You can choose from more than 10 flash cores, providing as much as 4 Mbits of memory. EmbFlash operates over 2.5 to 3.3V. Flash-core endurance is greater than 100,000 program/erase cycles, and TSMC guarantees data retention for more than 100 years after 10,000 cycles.—by Jim Lipman 3TSMC, San Jose, CA. 1-408437-8762, fax 1-408-441-7713, www.tsmc.com. 3Circle No. 405 All-in-one chip set makes digital cameras a snap ierra Imaging’s Raptor II makes key improve- S ments on the first-generation chip set that Ep- son (www.epson.com) and other camera manufacturers use. Raptor II includes two chips; one contains an image processor and 32-bit ARC Cores (www.arccores.com) RISC CPU with a separate 8-bit microcontroller handling system functions. Raptor II directly interfaces to Universal Serial Bus; iRDA; RS-232C; NTSC and PAL video, including SVideo; ATA; LCD; and as many as three motors. Add memory, a lens, an image sensor, and a display, and your hardware design is complete. The company optimized Raptor’s II architecture for CMOS and CCD sensors as large as 8 million pixels, but the chip set interfaces to those as large as 16 million pixels. Although camera users might like high-resolution pictures, they expect continued reduction in picture-to-picture delays. Raptor II responds with performance 10 times faster than its predecessor, outputting fully processed JPEG images as fast as 3.3 million pixels/sec or displaying 3202 240-pixel video images at 30 frames/sec. Sierra Imaging also focuses on extending battery life; Raptor II runs at 2.5V with 3.3V I/O signals and offers extensive system-powerdown-control facilities. The company’s next consideration was software support. The real-time Sierra system-software platform requires 300 kbytes of memory. Sierra Imaging also offers a fully functional reference-design kit with documentation and customization suggestions. Chip-set sampling ($100) will begin in April, and the company schedules volume production ($20) for July.—by Brian Dipert 3Sierra Imaging, Scotts Valley, CA. 1-408-461-2070, fax 1-408-461-2072, www. sierraimaging.com. 3Circle No. 406 Mezzanine modules speed VME data transfers Real-time radar, high-frequency sonar, image-processing, and transient-capture systems based on the VMEbus use auxiliary high-speed datapaths to transfer data between multiple processors and superfast I/O peripherals. These datapaths offload VME’s limited backplane-bus data rates to extend the overall bandwidth of the application. Overcoming the data-rate limits, two new plug-in mezzanine modules from Pentek allow you to select a standard busbypass technique that matches your system. The model 6220 velocity-interfacemodule mezzanine board attaches directly to the company’s DSP boards to provide a single-slot, high-speed Raceway interface. Mercury Computers (www.mc.com) developed the high-speed Raceway synchronous-backplane fabric, which operates independently of the VMEbus and provides multiple, simultaneous, 160-Mbyte/sec data channels between boards. Another 22 edn | January 21, 1999 new mezzanine module, the model 6226, supports the Front Panel Data Port (FPDP) standard for a front-panel-ribboncable interface based on a 32-bit parallel communication link that delivers data at 160 Mbytes/ sec. Pentek’s quad-DSP board accommodates two FPDP modules to give one bidirectional data-port per processor. Prices for the models 6220 and 6226 start at $2000 and $995, respectively. Both modules will be available in the second quarter.—by Warren Webb 3Pentek Inc, Upper Saddle River, NJ. 1201-818-55900, fax 1-201-818-5904, www.pentek.com.3Circle No. 407 Two new mezzanine velocity-interface modules give 160-Mbyte/sec datatransfers to VME-based DSP boards. www.ednmag.com