TI Creates Stereo Audio Codecs with 7-mW Playback for Portable Applications

Texas Instruments Incorporated (TI) (NYSE: TXN) today introduced two new stereo audio codecs for battery-operated applications, including digital still cameras and portable media players. Designed to extend battery life by lowering power consumption, the PCM3793 and PCM3794 audio codecs offer outstanding 7-milliwatt (mW) playback with a signal-to-noise ratio (SNR) of 93 dB.

The PCM3793 audio codec further increases power efficiency by integrating TI’s leading Class-D amplifier technology which is capable of driving 700 mW of output power per channel into an 8-ohm load. To complement the PCM3793, the PCM3794 has no speaker outputs, providing manufacturers with the flexibility to use an external amplifier, if desired.

“The efficiency of TI’s Class-D amplifiers makes them critical to the success of any battery-powered audio system,” said Susie Inouye, analyst, Databeans. “TI provides not only low power and noise, but also the value-added features manufacturers need to drive down system costs.”

Optimized for Low Power
TI’s PCM379x codecs offer key features that meet the specific needs of portable consumer audio OEMs, including:

  • Notch filter with programmable center frequencies: Without a notch filter, digital camera manufacturers have had to disable zooming during video recording to prevent camera lens motor noise from disrupting the audio track.
  • Tone control: OEMs can maximize audio performance for a particular application (i.e., jazz or classical) using bass, treble and mid-range equalization effects.
  • 3-D enhancement: Speakers that are close together can be made to seem further apart for a richer, “wide stereo” effect.

An on-chip, digital audio processor keeps signal processing in the digital domain, giving OEMs more control, lower noise and better power efficiency. The PCM379x codecs also can be operated with only one power supply, whereas other codecs require an additional power supply for analog and digital circuitry. An integrated cap-less headphone driver reduces external component count and increases bass frequency response.

PCM379x audio codecs support standard interfaces for audio (I2S, L-R justified, DSP) and control (I2C, SPI), as well as multiple single-ended and differential inputs and outputs (six inputs for both, with five outputs for the PCM3793 and three for the PCM3794). Additionally, inputs are selectable, and outputs can be mixed, giving designers control over a wide range of applications.

“With exceptionally low playback power and integrated features in the PCM379x codecs, TI has struck the optimal balance of power and performance that our customers require,” said Greg Davis, high performance portable audio marketing manager, Texas Instruments. “For instance, it’s exciting that we can help enable features, such as zooming while recording video on a digital still camera. Additionally, these devices integrate equalization and audio effects that can be helpful for portable media players.”

The PCM379x family of devices complements TI’s portfolio of high-performance analog and DSP products for the portable audio signal chain, including the Digital Audio platform of DSPs, audio data converters, clocks, Class-D audio power amplifiers and cap-free headphone amplifiers. TI provides the silicon, software, systems expertise and support that enable customers to get to market quickly. For more information see the Audio Solutions Guide. In addition, see TI’s power management products for portable consumer applications.

Availability, Packaging and Pricing
The PCM3793 and PCM3794 stereo audio codecs are sampling now and is expected to be in production in September 2006. Both are packaged in a standard 32-pin 5×5 mm2 QFN package. Pricing for the PCM3793 is $4.50 and the PCM3794 is $4.25 each in quantities of 1,000 units. A turnkey evaluation module is expected to be available in October 2006 that includes a PC-based interface for easily programming PCM379x devices.