Electronic Design UPDATE: May 4, 2005

May 4, 2005
Editor's View: Real Digital Power-Supply Control Goes Beyond Simple Sequencing And Ramping, by Don Tuite, Analog/Power Editor. Recent news from power-converter manufacturers announcing their support of PMBus and implementation of this I2C technology in ne

Electronic Design UPDATE e-Newsletter Electronic Design Magazine PlanetEE ==> www.planetee.com May 4, 2005


*************************ADVERTISEMENT************************** Samtec Application Notes and Online Tools Samtec has a full selection of application notes for SATA, XAUI, PCI Express, Rapid IO and other industry standards. In addition, Samtec offers PADS Libraries, High Speed Bandwidth Performance Selectors, Test Reports and Models for Simulation, and Signal Integrity support to create a comprehensive, user-friendly online resource for high speed design requirements. http://nls.planetee.com/t?ctl=90BC:1001CD **************************************************************** Today's Table Of Contents: 1. Editor's View *Real Digital Power-Supply Control Goes Beyond Simple Sequencing And Ramping 2. Focus On Embedded *Serial ATA II Hard Drives Arrive 3. News From The Editors *RS-232 Transceivers Run On 1.8 V *PhotoMOS Relay Has Low On Resistance *Electric Car Will Attempt U.S. Speed Record 4. Magazine Highlights: April 28, 2005 *Cover Story: Engineering Feature -- Patents: Cuffing Innovation? *Technology Report -- PCI Express Design: A Lesson In Techno-Shock *Technology Report -- Mobile Storage: Chips Served With Hard-Disk Salsa *Leapfrog: First Look -- Mini Ethernet Chip Contends In Low-End Networking Space *Leapfrog: First Look -- ADCs Digitize Capacitance And Impedance Directly *Design View/Design Solution -- Measure Capacitive Sensors With A Delta-Sigma Modulator Electronic Design UPDATE edited by Lisa Maliniak, eMedia Editor **************************************************************** Get The Lead Out! The European Union, as well as Japan and China, are about to restrict the use of environmentally hazardous materials in electronic components and systems through the Restrictions on Hazardous Substances (RoHS) directive. Check out Electronic Design's new RoHS Reference Center with links, articles, and more. Take our RoHS quiz to see how much you really know about this new EU directive. Then download the first chapter of our eBook, "Electronic Design's Guide To New International Environmental Laws." And stay tuned for more chapters to learn everything you need to know about this important emerging topic. http://nls.planetee.com/t?ctl=90C5:1001CD **************************************************************** **************************************************************** FREE Webcast: Capturing and Characterizing High-Frequency Signals Tuesday, May 10, 2005 at 2:00 pm ET Recent advances in sampling technology, memory usage, and other fields allow for much faster and more accurate measurements of fast pulses and high-speed serial data signals. This LeCroy technical seminar, featuring Dr. Michael Lauterbach, will focus on new techniques and technology for capturing very high-frequency signals -- up to 100 GHz -- using both real-time and "sampling" oscilloscopes. Register today at http://nls.planetee.com/t?ctl=90C4:1001CD **************************************************************** ********************** 1. Editor's View -- Exclusive to Electronic Design UPDATE ********************** Real Digital Power-Supply Control Goes Beyond Simple Sequencing And Ramping By Don Tuite, Analog/Power Editor Recent news from power-converter manufacturers announcing their support of PMBus and implementation of this I2C technology in new products demonstrates that digital power control is becoming mainstream. However, questions remain. What kind of control? And what is there beyond sequencing POLs, controlling their ramp time, and monitoring their output? Plenty, says Astec Power's Geof Potter. In a white paper ( http://nls.planetee.com/t?ctl=90C7:1001CD ), Potter notes that peripheral functions have long been within the scope of digital control. Yet component size, cost, and power consumption have limited control of an active feedback loop, including pulse modulation. Moreover, digital control requires data resolution and latency characteristics that have been available only in large, expensive DSP and analog-to-digital converter (ADC) products. So what's needed? In a full-blown digitally controlled power supply, a digital pulse-width modulator (DPWM) would calculate and time the switcher's duty cycle just ahead of the power switching stage. Ahead of the DPWM would be a proportional-integral-derivative (PID) control processor that centers the output voltage on a preset value by adjusting pulse width. (The proportional part of the PID control law scales its response linearly with the error. The integrator accumulates the error signal over time so that the longer the error exists, the harder the controller tries to correct it. And, the derivative function tends to reduce overshoot.) This processor gets its input from an analog-to-digital converter (ADC) that compares the supply's output voltage to a voltage reference. The PID filter then uses the digitized error to calculate the switcher duty cycle. What has made this hard to accomplish in the digital domain is that the transient response requirements for high-end supplies demand a fast controller and an ADC with minimal conversion delay. Proportional and derivative loops correct normal small transients. But in server supplies, for example, the problem is sudden, big load swings. In that case, the error output from the ADC needs to cause the transient monitor to interrupt the MCU. The MCU must respond immediately by adjusting loop gain and frequency. Additionally, the DPWM modulates the output duty cycle in response to the error signal from the ADC under normal conditions. Practically, the output duty cycle also is used to limit peak current. This requires a peak current detector to monitor inductor (or transformer) current. To provide this level of digital control, microcontroller supplier Silicon Laboratories announced the first of a family of products for power-control applications at April's Portable Power Developer's Conference. Based on a patented architecture, Silicon Labs' Si825x family of single-chip digital power-supply controllers combines high-speed processing hardware for real-time loop control with a flash-based system management controller. The control loop updates at 10 MHz and comprises a dedicated ADC, a programmable DSP filter engine, a six-channel DPWM, and a programmable overcurrent protection hardware detector. The system management controller performs fault detection and recovery, dynamic loop compensation and dead-time adjustment, PMBus communication, and external-device management. It is based on a 50-MIPS 8051 CPU. (That's right, an 8051 that's clocked and pipelined to achieve 50 MIPS.) The controller also includes 32 kbytes of flash and a 12-bit self-sequencing ADC, plus a SMBus/PMBus interface port, a UART, 16-bit timers, and additional PWM channels. For system design, Silicon Labs has a toolset that consists of a real-time firmware kernel, loop compensation and timing simulator/designer tools, system controller, configuration wizards, and the company's integrated development environment. There's also a USB debug adaptor and a complete half-bridge Si825x-based dc-dc converter. The kit comes with a PMBus interface protocol and external host interface hardware. The Si825x is available in a 5- by 5-mm, 28-pin QFN or a 32-pin LQFP. Pricing starts at $2.49 in 1000-unit quantities The Si825x is sampling now with general availability scheduled for the third quarter of 2005. To comment on this Editor's View, go to Reader Comments at the foot of the Web page: Electronic Design UPDATE ==> http://nls.planetee.com/t?ctl=90B8:1001CD **************************************************************** *************************ADVERTISEMENT************************** Red Hot Deals - Full Design Kits for under $10! 'Spring into action' with ZiLOG and take advantage of special red hot deals focused around our critically-acclaimed development kits for the 8-Pin Z8 Encore! XP(r) Flash MCU. Through June 30, 2004, our development kits have been discounted to an ultra cool price of just $9.95; that's 80% off the retail price of $49.95. No strings - just amazing value. Catch 'spring fever' and get yours today! http://nls.planetee.com/t?ctl=90BD:1001CD **************************************************************** ********************** 2. Focus On Embedded ********************** ***Serial ATA II Hard Drives Arrive Samsung Electronics is the first to deliver Serial ATA (SATA) II drives that have twice the transfer rate of the initial crop of Serial ATA drives. The SATA II drives have 3-Gbit/s links. SATA drive usage continues to push parallel ATA (PATA) drives to the side. For example, SATA already has features, such as hot-swap support, that PATA drives lack. SATA II drives support a number of new standards, including Port Multiplier support that lets a single controller port handle multiple SATA II drives. As a result, motherboards can have fewer SATA II ports while still being able to handle more drives for future expansion. The Port Selector standard lets multiple hosts access a single drive, a requirment typically found in cluster configurations where redundancy is key. All the drives in the series have a 7200-rpm spindle speed with an 8.9-ms average seek time and an 8-Mbyte cache buffer. Samsung's NoiseGuard and SilentSeek technologies keep the drives quiet. The drives are available in 80-, 120-, and 160-Gbyte versions. Estimated street prices are $93, $120, and $150, respectively. Samsung Electronics Co. ==> http://nls.planetee.com/t?ctl=90C8:1001CD ********************** 3. News -- From The Editors ********************** ***RS-232 Transceivers Run On 1.8 V The devices in a family of single and dual RS-232 transceivers operate over an input supply range from 1.8 to 5.5 V. The lower voltages accommodate systems powered from two alkaline, nickel-cadmium, or nickel-metal-hydride cells or systems that interface directly to a low-voltage logic supply. All the ICs offer a low 1-microampere shutdown current and a 15-microampere receiver-active current. The LTC2802 and LTC2804 support up to 1-Mbit/s data rates for proprietary diagnostic links, and the LTC2801 and LTC2803 are capable of rates as high as 250 kbits/s. An integrated boost converter generates the required RS-232 output signal levels. The LTC2801 and LTC2802 are single transceivers, offered in a tiny 3- by 4-mm DFN package. The LTC2803 and LTC2804 are dual transceivers offered in a 16-lead SSOP and 16-lead DFN package. Pricing begins at $1.60 each in 1000-piece quantities. Linear Technology Corp. ==> http://nls.planetee.com/t?ctl=90C9:1001CD ***PhotoMOS Relay Has Low On Resistance A new Panasonic brand PhotoMOS relay from Aromat offers high continuous load current of 0.5 A and low on resistance of 1 ohm. The relay is well suited for power supplies, test and measurement equipment, communications, security, and other applications requiring 1 Form B contacts. The four-pin version is designated the AQY412 series (1 Form B), and the eight-pin is the AQW612 (1 Form A 1 Form B). They both come in SOP (super miniature) and DIP reinforced-insulation 5000-V packages. SOP and DIP types are available in both tape-and-reel and tube-packing style. The SOP version measures a compact 4.3 by 4.4 by 2.1 mm. Operating temperature is -40 deg. C to 85 deg. C. The AQY412 is priced at $2.32 and the AQW612 is $4.84 in 1000-piece quantities. Delivery is stock to six weeks. Aromat Corp. ==> http://nls.planetee.com/t?ctl=90C1:1001CD ***Electric Car Will Attempt U.S. Speed Record Early tomorrow morning, May 5, a car powered solely by electricity from a bank of batteries will attempt to set a new FIA (Federation Internationale d'Automobile) electric vehicle land-speed record. The record currently stands at 245 mph. The objective is for the electric vehicle, named e=motion, to achieve speeds in excess of 300 mph (400 feet per second). The 32-ft long, mustard-yellow car, whose main sponsor is ABB Inc., will make the record attempt on a closed, secured section of paved road near West Wendover, Nevada. The e=motion car has no mechanical gears. Acceleration is controlled entirely by ABB variable speed drives regulating two of the company's 50-horsepower electric motors. ABB's system uses a regenerative standard inverter from its ACS800 motor drive line to convert the 600-V dc output from the car's four packs of 52 lead-acid batteries into ac power for the two motors. Video, system diagrams, and vehicle specifications can be viewed at the ABB Web site. ABB Inc. ==> http://nls.planetee.com/t?ctl=90C6:1001CD *************************ADVERTISEMENT************************** RapidChip Xtreme2 (TM) Family Includes 12 New Slices Speed TTM using LSI Logic's highly integrated serial interconnect platform with up to 48 integrated SerDes, up to 5.4 million logic gates, and up to 4 megabits of embedded MatrixRAM. Parallel I/O capabilities support a variety of high-performance bus and memory protocols. These new slices enable storage, computing, networking, and embedded systems applications. View the webcast at http://nls.planetee.com/t?ctl=90BA:1001CD **************************************************************** ********************** 4. Magazine Highlights ********************** In case you missed them, here are some of the high points of our most recent issue. April 28, 2005: * Cover Story: Engineering Feature -- Patents: Cuffing Innovation? Patent claims are threatening what have been accepted as royalty-free standards. http://nls.planetee.com/t?ctl=90B6:1001CD * Technology Report -- PCI Express Design: A Lesson In Techno-Shock Start the coffee. Embedded designers are in for the long haul when it comes to implementing PCI Express, but the rewards are worth it. http://nls.planetee.com/t?ctl=90B5:1001CD * Technology Report -- Mobile Storage: Chips Served With Hard-Disk Salsa Tiny hard disks and massive flash memory devices give designers a spicy array of storage choices. http://nls.planetee.com/t?ctl=90B9:1001CD * Leapfrog: First Look -- Mini Ethernet Chip Contends In Low-End Networking Space With SPI, an Ethernet controller easily interfaces to 8-bit microcontrollers. http://nls.planetee.com/t?ctl=90B4:1001CD * Leapfrog: First Look -- ADCs Digitize Capacitance And Impedance Directly These monolithic devices simplify measurement-system design in applications ranging from automotive to medical. http://nls.planetee.com/t?ctl=90B7:1001CD * Design View/Design Solution -- Measure Capacitive Sensors With A Delta-Sigma Modulator http://nls.planetee.com/t?ctl=90B3:1001CD For the complete Table of Contents, go to Electronic Design ==> http://nls.planetee.com/t?ctl=90BB:1001CD ***** A Closer Look At Video Signals Nowadays there are numerous standards for the digital video signals widely used in such products as game players and cell phones. Tough design questions arise, however, because those digital signals must be dealt with in an analog domain. Get the answers in a new eBook, "Analog/Mixed-Signal Components For 21st Century Video," by Analog/Power Editor Don Tuite. http://nls.planetee.com/t?ctl=90C0:1001CD ***** Embedded in Electronic Design (EiED) Online is your source for technical insight and hands-on reviews. Read Bill Wong's recent EiED Online column: "Soft MCU Goes Graphical." http://nls.planetee.com/t?ctl=90B2:1001CD ***** THOUGHT YOU'D MISSED THEM? DON'T WORRY, THEY'RE ARCHIVED Electronic Design's webcasts are available online: Embedded Systems Conference Showcast: Take a look at the new products and technologies from this year's show. http://nls.planetee.com/t?ctl=90C2:1001CD Advances In Mixed-Signal Testing: Learn how to add 32 digital channels to four-channel oscilloscopes. http://nls.planetee.com/t?ctl=90BF:1001CD Maximize System Mobility By Selecting The Best Memory Options: Sort through your memory options for mobile systems. http://nls.planetee.com/t?ctl=90BE:1001CD **************************************************************** SUBSCRIBE ONLINE TO ELECTRONIC DESIGN If you're reading this e-newsletter, then you are either a current Electronic Design subscriber, or should be (145,000 of your peers are). To apply for or renew a subscription to Electronic Design absolutely FREE and without paperwork or hassle, click on the link below. http://nls.planetee.com/t?ctl=90C3:1001CD ****************************************************************




Editorial: Mark David, Editor-in-Chief mailto:[email protected] Advertising/Sponsorship Opportunities: Bill Baumann, Publisher: mailto:[email protected]

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