Texas Instruments Announces Ultimate Hi-Rez Audio Chip

You can't stop progress—especially at Texas Instruments. The Dallas, TX–based technology giant has introduced a new two-channel digital audio amplifier chip with the world's best specifications.

The TAS5015 is the world's first 192kHz/24-bit digital amplifier capable of a dynamic range of 110dB measured at the speaker. The 48-lead thin quad flatpack (TQFP) chip can drive speakers directly with up to one or two watts of output power, but is better used as a controller for a dedicated output stage, says the company's digital audio marketing manager Niels Anderskouv. The TAS5015 supports "all major audio standards on the market, including DVD-Audio, with sample rates ranging from 32kHz to 192kHz," according to a late March press release. In a properly designed amplifier, the 5015 makes possible outputs of 300 watts or more—with combined total harmonic distortion and noise below 0.03%. When used with a variable power supply, the 5015 enables a dynamic range of 130–140dB, previously thought to be theoretically possible but practically impossible.

The 5015 isn't cheap: $25 each in quantities of 1000. Furthermore, incorporating the device in multichannel amplifiers requires one for each pair of channels—three for a six-channel amp, for example. "The TA5015 represents a revolution for DVD-Audio," said Anderskouv in a telephone briefing March 30, "There is no feedback, no analog processing. To use this product, a manufacturer must sign a licensing agreement." With the 5015, TI will emulate Dolby Labs by requiring manufacturers to sign licensing agreements and to submit their finished products to a team of evaluators, who will insure that the products meet an extraordinarily high level of performance.

Manufacturers who choose the 5015 will find reaching that level easier by availing themselves of a massive "data dump" of engineering specifications, design parameters, and working samples, all the result of extensive research by TI. The 5015 is a "clear differentiation between the high-end and the mass market," Anderskouv said. The new chip is part of a family of high-performance digital audio products, including the TAS3001, 3002, and 3004—"wide data path devices." Samples of the TAS5015 are available now; volume production is expected to be in full swing by July. Other chip sets with 192kHz capabilities will be introduced for mass-market products later this summer.

A discrete amplifier, available from TI, can convert the 5015's PWM output signal into the digital power level required at the speaker, while "dissipating less than one-tenth the power of conventional class-A and class-AB amplifiers." TI's Performance Audio Group has developed a VLSI output device "the size of a couple of DVDs, but capable of 200 watts continuous power," said Anderskouv. A smaller device, the TAS5100, can output 30 watts into 4 ohms with "90% efficiency." Applications include active loudspeakers.

A major goal at TI is to create advanced, great-sounding amplifiers with enormous savings in weight, heat, and energy. The company has multiple patents for such devices, and has invested heavily in audio, including the acquisition of Burr-Brown Corporation last year. Anderskouv himself is an alumnus of the small Danish firm Toccata Technology, which developed the technology for the TACT Millenium digital amplifier. In March 2000, his company was also acquired by TI, which has made a $2 billion investment in digital audio in the past year.

"There are tremendous opportunities in high performance audio, automotive sound, digital radio, and convergence products," he said. His group has done extensive work with digital signal processing for speaker/room correction, and he claims that in their Dallas laboratory they have a prototype system that "can make a $79 Radio Shack speaker sound like one costing $10,000. You can't hear the difference." We hope to accept the challenge sometime this summer.