Electronic Design UPDATE: November 10, 2004

Nov. 10, 2004
Industry View: AC'97: Once And Future King For Handheld Audio Interfaces, by Julian Hayes, Wolfson Microelectronics plc. Today's smartphones and similar handheld systems use a variety of interfaces to exchange data between processors and audio ICs...

Electronic Design UPDATE e-Newsletter Electronic Design Magazine PlanetEE ==> www.planetee.com November 10, 2004


*************************ADVERTISEMENT************************** True Circuits PLLs silicon-proven in ARM 926, 1022, 1026, and 1136 processor cores These high-quality, low-jitter PLL hard macros are available for immediate delivery in a range of frequencies, multiplication factors, sizes and functions in TSMC, UMC and Chartered processes from 0.25um to 90nm. Call (650) 691-2500 or visit the timing experts at http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BACD0Aa **************************************************************** Today's Table Of Contents: 1. Industry View * AC'97: Once And Future King For Handheld Audio Interfaces 2. Focus On Embedded * HyperTransport Consortium Announces New Spec 3. News From The Editors * Software Corrects Errors In RF Test Signals * PWM Processor Pumps Up The Volume In A/V And DVD Receivers * Components Orders Back Up Again 4. Upcoming Industry Events * 37th International Symposium on Microelectronics * North American Ipv6 Task Force Technologist Seminar * Power Electronics Technology Exhibition & Conference * Flat Information Displays * Materials Research Society Fall Meeting 5. Magazine Highlights: October 28, 2004 * Cover Story: Engineering Feature -- MEMS: Size Does Matter * Leapfrog: Industry First -- PCB Team-Design Tool Elminates Partitions, Yet Spurs Concurrency * Design View/Design Solution -- Simulation Vs. Silicon: Avoid Costly Mistakes With Accurate Models Electronic Design UPDATE edited by John Novellino, Senior Technology Editor **************************************************************** THOUGHT YOU'D MISSED THEM? DON'T WORRY, THEY'RE ARCHIVED Electronic Design's two latest webcasts are available online: COM Express -- Emerging Standard: Bill Wong examines COM Express, the new Computer-on-Module standard from the PCI Industrial Computer Manufacturers Group. Wong looks at what's inside the standard, its effect on high-speed serial technologies, and how it's changing the embedded landscape. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMBG0Ao Selecting the Best ASIC Solution: Dave Bursky discusses the ASIC selection process, exploring the decision points you should consider in determining the right ASIC design route. Bursky and a panel representing leading ASIC manufacturers explore the issues you face when planning a new chip design. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMVH0AB ***** YOUR CHANCE TO WIN $500! Take our ISSUE POLL and win a $500 gift certificate. The editors would like to know what you think of the OCTOBER 28 ISSUE of Electronic Design. Your feedback will help us better understand your critical information needs and provide valuable guidance for developing future editorial content. It's also your automatic entry into our drawing for a $500 American Express gift certificate. Go to ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMn20AD ***** BE SURE TO VISIT Electronic Design's Web site, where the power of Electronic Design is a mouse click away! Read our Web exclusives, enjoy our Quick Poll, discover Featured Vendors, access our archives, share viewpoints in our Forums, explore our e-newsletters, and more. How expensive and technically difficult was it/will it be to meet the European Union's Restriction on Hazardous Substances (RoHS) directive to remove lead and other hazardous materials from your products? --Not very --Moderately --Significantly --A real problem --Hope we can Go to Electronic Design ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BGmZ0Ak ***** Join Electronic Design and LeCroy for a free, one-hour webcast discussing Advances in Signal Integrity Testing, starting at 2:00 p.m. EST tomorrow, Thursday, November 11. Topics will include methods engineers can use to test the effect of probe loading on signal shape, techniques for checking the effect on signal integrity of some new scopes that use DSP to boost bandwidth, and next-generation capability to deskew both timing delay and dc gain/offset at the probe tip when testing multiple signals. Examples of real signals in practical applications, including serial data streams and microprocessor/memory systems, will be provided. Reserve your seat now! http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMn30AE **************************************************************** ********************** 1. Industry View -- Exclusive to Electronic Design UPDATE ********************** AC'97: Once And Future King For Handheld Audio Interfaces By Julian Hayes, Vice President of Marketing, Wolfson Microelectronics plc Today's smartphones and similar handheld systems use a variety of interfaces to exchange data between processors and audio ICs. Serial interface pulse-code modulation (PCM) is the de facto standard for voice, while hi-fi functions rely on either Intel's AC'97 standard or the I2S (Inter-IC Sound) interface introduced by Philips in the 1980s. However, Intel recently released a new standard, High Definition Audio (previously known as Azalia), to supercede AC'97. But it's unlikely that this new standard will make significant inroads in the handheld market. High Definition Audio's enhancements over AC'97 only add value in mains-powered, stationary systems. For example, take data throughput. AC'97 supports data resolutions up to 20 bits and a maximum sampling rate of 48 kHz, enabling sound quality beyond the original audio CD specification. High Definition Audio's higher data rate and resolution (192 kHz and 32 bits) simply do not translate into better sound in handheld systems, whose overall performance is limited by small speakers and low-cost headphones. On the other hand, the extra power consumed by using a clock twice as fast as AC'97 is an important drawback, as all system components must help maximize battery life. Another High Definition Audio novelty is jack sensing, which allows microphones, headsets, and active speakers to all be plugged into one socket. Again, most handheld systems do not need this capability because they only have a single headset socket, and all other transducers, such as internal loudspeakers, are hardwired. The absence of benefits relevant to handheld systems, combined with the drawback of higher power consumption, will keep High Definition Audio out of this market -- unless, of course, processor vendors force the issue by supporting a single interface mechanism. The current trend, however, is in the opposite direction. An increasing number of vendors, including Intel, where AC'97 originated, support both I2S and AC'97, leaving the decision to their customers. Since the choice of audio interface can affect power consumption, pin count, and CPU loading, it pays to be aware of their pros and cons. While I2S is designed solely for the transmission of audio data, AC'97 also supports control functions. With it, processors can enable and disable functions or change settings within the audio IC. I2S requires a separate control interface, raising the pin count of both the processor and the audio IC. This is undesirable in handheld systems, where every component should be as small as possible. AC'97 is power-efficient for multiple sampling rates. This is important because the 44.1-kHz rate used on audio CDs, voice signals sampled at 8 kHz, and 48-kHz audio files are all in widespread use. Since I2S sampling rates are determined by the interface's clock frequency, each sampling rate needs a different clock. Accurately generating low-jitter clock signals at several unrelated frequencies requires a low-jitter analog phase-locked loop, which consumes a substantial amount of power. An alternative solution is to keep the interface running at a fixed rate and convert audio streams to that sampling rate in the digital domain. However, this compute-intensive task increases the power consumed by the processor and can slow down or stall other programs running on it. In AC'97 devices, the clocks are fixed to the default sampling rate of 48 kHz. Lower rates are achieved by interspersing valid data with empty frames. For playback at 44.1 kHz, the data is marked invalid approximately one frame out of every 12, using the AC'97 tagging mechanism. The valid data points are then spread out evenly in time by the digital-to-analog converter, creating a low-distortion analog signal. This method is more power-efficient than a phase-locked loop or digital sampling rate conversion. The advantages of AC'97 come at the cost of a higher gate count and power consumption of the interface circuitry itself. These negatives are outweighed by the power saved in other system components wherever multiple sampling rates are used. As long as no interface designed specifically for handhelds is available, AC'97 is unlikely to fade away regardless of contrary developments in other market segments. Julian Hayes previously headed Wolfson's audio business. He holds an honors degree in physics from Southampton University. Prior to joining Wolfson, he worked at Analog Devices Inc. for more than 10 years. To comment on this Industry View, go to Reader Comments at the foot of the Web page: Electronic Design UPDATE ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMn40AF **************************************************************** *************************ADVERTISEMENT*************************** Advance Your Career at DiceEngineering.com DiceEngineering is one of the leading engineering job boards for highly qualified engineers. Today you can search more than 11,000 challenging, interesting, high-paying jobs from leading companies including IBM, Aerotek and Motorola. These top companies are searching for high-level engineers like you. They can only find you if you're registered. For your next big career advancement, go to http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BKs60AK **************************************************************** ********************** 2. Focus On Embedded ********************** ***HyperTransport Consortium Announces New Spec The HyperTransport Expansion Specification (HTX) is the latest standard from the HyperTransport Consortium. It lets the HyperTransport bus move off the motherboard. This reduces system cost as well as latency by not requiring a bridge chip to another interface such as PCI Express. The new HTX standard is already supported by IWill, a motherboard manufacturer, and PathScale, whose InfiniPath HTX adapter links InfiniBand directly to processors based on HyperTransport, like the AMD Opteron. Multiple processors can transparently access a single HTX adapter via HyperTransport. An HTX slot can provide any kind of interface from InfiniBand to a high-performance graphics adapter. HyperTransport Consortium ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10qFs0A7 Advanced Micro Devices Inc. ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BBrC0AN PathScale Inc. ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMn60AH IWill Corp.==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMn70AI ********************** 3. News -- From The Editors ********************** ***Software Corrects Errors In RF Test Signals The N7622A Signal Studio toolkit provides error correction capabilities for the ESG and PSG vector signal generators at modulation bandwidths up to 800 MHz. Thus, it ensures high-quality simulated signals for testing radar, ultra-wideband communications, and third-generation wireless power amplifiers. To test these systems, designers typically create and send I/Q waveforms to an arbitrary waveform generator (AWG), which converterts them to analog signals. These signals are then fed to the I/Q modulator of a signal generator, which outputs them at the desired carrier frequency. The Signal Studio corrects the errors introduced in this path. The base function of the toolkit will be available as a free download from Agilent's Web site. The error correction option for use with the internal baseband generator costs $4000. With an external wideband AWG option, the price is $9000. The software will be available on November 15. Agilent ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10IjM0AQ ***PWM Processor Pumps Up The Volume In A/V And DVD Receivers For audio/video and DVD receivers, the TAS5518 pulse-width-modulation (PWM) processor supplies up to eight speaker channels with 48-bit processing for sound field enhancement. On top of that, there's an additional 24-dB dynamic range boost with an unusual power-supply volume-control feature. At normal listening levels, the volume control provides 134-dB dynamic range. The device also offers a very low noise floor, with as little as 10 mV of output noise. The TAS5518 operates in conjunction with Texas Instruments' power stages, such as the 100-W TAS5182. It uses external discrete MOSFETs for the H-bridge and achieves more than 95% efficiency. The TAS5518 digital audio processor is now available in volume. Packaged in a 64-pin TQFP, the device costs $7.95 each in quantities of 1000. The TAS5182 power stage is available at $5.30 in similar quantities. Texas Instruments Inc. ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh108CD0AL ***Components Orders Back Up Again The monthly order index compiled by the Electronic Components, Assemblies & Materials Association (ECA) continued its rollercoaster ride in October, rising again after a dip in September. The index's 12-month moving average remained relatively flat, as it has over the last few months after reaching a peak in mid-summer. "We're seeing a lot of fluctuation in the monthly index over the last few months, but the 12-month index has been fairly stable and positive during the same time period," said Bob Willis, ECA president. "The manufacturing executives I've spoken with at recent events such as CARTS Europe remain upbeat about 2005." The ECA represents manufacturers and producers of passive and active electronic components, component arrays and assemblies, and materials and support services. It is a sector of the Electronic Industries Alliance. Electronic Components, Assemblies & Materials Association ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMn80AJ *************************ADVERTISEMENT*************************** Catch the PLX (R) PCI Express ExpressLane (TM) Seminar PLX invites you to attend our FREE tutorial on the "Essentials for Building a PCI Express (TM) System," which includes an introduction to PCI Express (PCIe) technology; building blocks for storage, communications and other embedded systems; our PCIe switches and bridges; practical design considerations; a demonstration of the PLX PCIe switch and our FastLane (TM) family of PCI and PCI-X bridging devices. To register for the "PLX ExpressLane Seminar Series: Essentials for Building a PCI Express System", please go to http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BLsA0AW **************************************************************** *************************ADVERTISEMENT*************************** New RapidChip Partner Program Appeals to Many The explosive growth in Platform ASICs has quickly fueled interest in the new RapidChip(R) Partner Program. LSI Logic and Partners are creating a diverse, expanding environment of third-party IP, design services and EDA tool providers. This support extends the capabilities of RapidChip Platform ASICs and helps OEMs reduce time-to-market, minimize design risk and lower the costs of innovating new products. See why a growing number of third-party providers are aligning behind LSI Logic's RapidChip Platform ASIC to address the cost-effective solutions that today's applications require at: http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMoA0AT **************************************************************** ********************** 4. Upcoming Industry Events ********************** Nov. 14-18, 37th International Symposium on Microelectronics Long Beach, Calif. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMoB0AU Nov. 16-17, North American Ipv6 Task Force Technologist Seminar Arlington, Va. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMoC0AV Nov. 16-18, Power Electronics Technology Exhibition & Conference Chicago, Ill. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BDFC0Af Nov. 18-19, Flat Information Displays (FID 2004) San Francisco, Calif. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMoD0AW Nov. 29-Dec. 3, Materials Research Society Fall Meeting Boston, Mass. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BHts0AJ ********************** 5. Magazine Highlights ********************** In case you missed them, here are some of the high points of our most recent issue. October 28, 2004: * Cover Story: Engineering Feature -- MEMS: Size Does Matter Packaging and testing developments, greater standardization efforts, improved software, and the emergence of MEMS "clusters" worldwide point to a ready-to-explode market. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMoE0AX * Leapfrog: Industry First -- PCB Team-Design Tool Elminates Partitions, Yet Spurs Concurrency Whether separated by cube walls or continents, a PCB design-infrastructure tool enables team members to work simultaneously and collaboratively. http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMoF0AY * Design View/Design Solution -- Simulation Vs. Silicon: Avoid Costly Mistakes With Accurate Models http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMoG0AZ For the complete Table of Contents, go to Electronic Design ==> http://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BMoH0Aa **************************************************************** 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://lists.planetee.com/cgi-bin3/DM/y/eA0Gl4E70Fh10BEE30AP ****************************************************************




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