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TI Hears Customers' Need For Cost-Competitive, High-Power and High-Quality Digital Sound in New Markets
New Home Theater Digital Audio Devices Include Industry's First All-Digital Amplifier With 100-Watt Output
| The manufacturer says . . . | ChipCenter's Paul O'Shea says . . . |
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Extending its digital amplifier technology into the burgeoning home theater industry, Texas Instruments Incorporated (TI) introduced a new line of cost-effective digital audio amplification products that will enable new market opportunities for completely digital audio systems, from source-to-ear digital sound reproduction. Among the new products is the industry's first 100-watt (W) all-digital audio amplifier. This Digital Amplifier Power Stage Controller efficiently manages the delivery of a full 100 W at 6 ohms for driving speakers in home theater applications. TI's new product lines will increase digital amplifier power output, number of channels available and sound quality, while reducing power consumption, system cost and form factor size in targeted audio devices, ranging from DVD and A/V receivers to mini-component systems. "The Texas Instruments Digital Amplifier is wonderful technology," said Katsuhiko Iida of Lpro System, Inc., a Japanese audio consulting firm. "The tonal balance is so natural that it sounds like the original analog sound. It produces an accurate and focused sound, realizing a pure and vivid reproduction of the original music or soundtrack." Iida has over 30 years of experience as an audio tuning specialist. "TI's new developments in digital audio solutions have enabled us to take a significant step forward in designing the industry's lowest-profile A/V receiver," said K. Higashiyama, Senior Staff Engineer, MATSUSHITA AVC Company. "Building on our current implementation of TI digital amplifiers in some of our Panasonic products, we intend to design future generations of our compact, full digital sound systems using TI's new solutions." TI's digital audio product line features a two-stage architecture. The first is the digital audio pulse-width-modulation (PWM) processor, which employs advanced digital signal processing and fourth order noise-shaping to convert the digital data from the source into the PWM format. The second stage is the digital amplifier power stage, which applies the digital PWM signal directly to the speakers, maintaining a complete digital path from the source to ear. The versatility of the two-stage architecture enables designers to develop a modular approach to product design, where the logic-level digital portions of the design -- digital signal processor (DSP), PWM processor and logic-level interfaces -- can be placed on a single board. In addition, the digital power stages can be designed on a separate board, enabling several different power levels to be designed using a single, logic-level digital board. The two-stage architecture saves resources and time to market with next-generation products. TI Reference Designs TI's new power stage products include: The new six-channel PWM processors include: Advanced Audio Amplifiers Drive Power Efficiency in all Digital Systems. The launch of the TAS5182 Digital Amplifier Power Stage Controller marks the industry's first all-digital power solution to provide up to 100 W (6 ohms) output drive. The device is designed with a new architecture that uses external, discrete MOSFETs (metal-oxide semiconductor field effect transistor) for the H-bridge and achieves efficiency of more than 95% in high-power amplification. With its efficient architecture and thermal PowerPad(tm) package, the TAS5182 achieves low heat loss and low power requirements, enabling audio-video (A/V) receivers to be reduced to one-third the height of previous systems. This product will extend the typical power level of a DVD receiver to levels currently only attained in A/V receivers. This high power stereo device also enables digital amplifiers in the A/V receiver market, since it can address the typical requirement of 100 watts per channel. The TAS5182 also integrates features that help protect the system and simplify the design in high-power audio applications, including over-current protection, over-temperature sensing and under-voltage lockout. TI's new TAS5110 digital amplifier can supply 50 W amplification for a wide range of end equipment, such as speakers in DVD and A/V receivers, mini- and micro-component systems, Internet appliances, automotive systems and other mid-power applications. With efficiencies greater than 90 percent, the TAS5110 provides an excellent low thermal dissipation solution for systems that require both high audio performance and space constraints. To ease thermal design, the TAS5110 is available in two PowerPad(tm) package options: one with a thermal pad on the bottom for sinking heat into the board, and the other with a thermal pad on top for more traditional methods of heat dissipation. This flexibility in thermal design makes it easier for manufacturers to transition their speaker and component products to digital technology. Innovative PWM Processors Integrate Digital Sound for Multi-Channel Applications. The new six-channel TAS5036 PWM audio processor adds to the features of the TAS5026 with an even higher SNR of 102 dB. Combined with the inherent advantages of digitally produced sound, the TAS5036 is targeted at high performance A/V and DVD receivers. Website: www.ti.com |
I should probably put a warning label on this review because it doesn't fit the typical Analog Avenue review since it is about a digital product, in a space that has been dominated by analog designs. I think this product is important for analog designers because you need to know about competing technologies. I hope you agree. Most companies realize that they can't be the powerhouse in every field, so the smart ones position themselves through mergers and acquisitions. TI was already a major force in audio when they decided that they wanted to be on the leading edge of the up and coming digital audio market. So they licensed the technology of a company from Denmark called Toccata, in 1999. Toccata made an all digital audio system that was used in a very high-end system. You and I have probably never heard of it since the product retailed for about $10,000, but it was considered to be a leap-frog over the existing digital audio technology. In March of 2000, TI purchased Toccata Technology and all its IP. Toccata's amplifier uses only digital technology, eliminating analog feedback and the need for analog signal processing or amplification at any stage. According to the research firm Forward Concepts, the PC and audio industries are moving away from analog speakers and replacing them with digital speakers. The firm predicts 65 percent of PC and consumer speakers will have digital speaker technology by 2003. By September 2000, TI released the first chip and the following March they released a solution that included a pulse-width-modulation (PWM) and H-Bridge - a full digital amplifier. Those parts were the TAS5000 and TAS5100. Since then they have introduced a series of parts, one is at the high end, the TAS5015, followed by a series of parts aimed at the consumer market. TI began working with Panasonic who subsequently introduced a DVD mini-component audio system in December of 2001. You can expect to see it introduced in the States this month (June 2002). This mini-component DVD has six channels with 30 W per channel, has DVD drives on the system, a mini disk, and a tuner. It is a standard mini-component size, about 6" tall x, 10" deep x and the width of a DVD drive. This DVD uses the previous generation chips, the TI TAS5001 and the TAS5100. Panasonic also released a high-end AV receiver in Japan, the XR10, which is a 100W system, based on TI technology and is based on the TAS5012. It is one of the first commercially available mass market all-digital amplifier chip solutions. The XR10, compared to a standard AV receiver that is 6 to 8" tall for a 100W X 6, is a mere 2" tall. So TI is using this success as a stepping stone to more markets. You will see DVD receivers being developed, which means instead of having a separate DVD player and audio receiver they will be integrated into one product. Sony has one and other companies have released the same design, all because the digital amplifier has enabled the market. For example, shrinking the heat sinks by up to one-tenth the typical size, and using designs that need only half the power required by the traditional A/B amplifier, allows manufacturers to shrink product size considerably resulting in new market opportunities. TI also sees this technology being used in AV receivers where it will shrink the end equipment about one-half to one-quarter the existing size. One of the new digital audio products from TI is the TAS 5182 - a 100W digital amplifier power stage controller. TI is the first to offer this and they see it as important because the US consumer expects 100W AV receivers. However, you will notice that it is 100W at 6 ohms and not the typical 8 ohms. The reason TI didn't offer 8 ohms is simple, the technology isn't there yet. For now TI and their competitors can only offer about 70W to 80W at 8 ohms. The TAS5182 is a new technology, and even a new product space. It has a processor that converts the PCM signal to PWM and passes it on to the power stage devices. The 5182 power stage has a MOSFET H-Bridge that drives the MOSFETs, turning them on and off and applying a digital signal out to the speakers. This H-Bridge driver is noteworthy because it is one of the first that focuses solely on high quality audio performance. It also has features specifically for the audio market: it will sense over-current conditions, and sense the MOSFET temperature and shut them down if they get over a designated temperature. For over-temperature sensing it uses an external thermistor that you attach to the heat sink. You set the temperature at the point at which you want it to cut out. For the current, it senses the current through the MOSFETs and if it gets too large it will shut down the MOSFETs. It also senses the voltage and if it drops to a level where it will harm the MOSFETs it will turn them off. With the external MOSFETs, TI recommends IR MOSFETs because they have up to 95% efficiency. So a 100W amplifier only needs to dissipate 5W. TI says the TAS5110 is a next generation power stage, and an extension of the TAS5100, which is shipping in a Panasonic product. The 5110 can drive 50W at 4 ohms and is used in DVD receivers, which is the sweet spot of those receivers. The TAS5110 has an efficiency of 90% so it dissipates only 5W at 50W. That's significant because it makes the thermal design of these much simpler than needed with traditional design technology. The last product in this digital audio offering is the 5026 - a 6-channel processor that converts PCM data into PWM data. This chip was designed specifically for a multi-channel DVD receiver or a DVD mini-component system, like the Panasonic system. TI integrated 6 channels because, again, it's the sweet spot for audio. It takes 6 channels in and has a signal-to-noise ratio (SNR) of 96dB. Coupled with the 5110, it has typical total harmonic distortion (THD) performance of 0.06%, and it enables you to independently control the volume in 6 channels. This volume control is a patented TI technology. TI says the algorithm used to control the volume levels gives it a very smooth, analog-like, sound to volume changes. The 96dB SNR performance you get is at the back end so you easily meet the 90dB that Dolby has specified for high-end output. TI also offers a 5036 which is similar to the 5026 with the main difference being a better SNR level. Planned pricing per unit in quantities of 50 thousand or more for TI's new digital audio products are:
TAS5026 64-pin TQFP, samples available now, production by end of June 02, @ $5.72. Product brochure: http://www.ti.com/rd/newamps1/. |
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