8-channel PWM audio processor has dual sample rate converters

April 18, 2013 // By Graham Prophet
Texas Instruments has introduced an integrated, HD-compatible chip to mix two audio sources for home and pro audio products.

TI's TAS5548 is an 8-channel pulse-width modulator (PWM) audio processor with dual asynchronous sample rate converters (ASRCs) integrated on a single chip. The HD-compatible IC allows home and professional-audio designers to seamlessly mix two audio sources, providing design flexibility and cost savings compared to competitive solutions that require two chips. It accepts sample rates from 8 kHz to 192 kHz and converts them to a fixed rate of 96 kHz or 192 kHz, eliminating the need to create, store and change coefficients. This simplifies the design of digital multi-channel products, such as Blu-ray home-theater-in-a-box (HTiB), A/V receivers, mini/micro combos, and soundbars.

The TAS5548’s 40-kHz audio bandwidth is compatible with Dolby True HD and DTS-HD, and TI claims unmatched multi-channel performance. You can add audio processing capabilities such as 7-band parametric equalisation (EQ), bass and treble tone control, volume and loudness control, dynamic range compression (DRC), and input and output mixing.

Simplified multi-channel design is assisted by twin integrated 4-channel ASRC cores allowing audio system designers to switch sample rates without changing coefficients. Native processing at 96 kHz for 8-channel output enables ultra-low out-of-band noise and jitter suppression for good noise performance. Extra microphone and I2S input combined with the ASRC’s ability to mix two different sample rate sources provides the flexibility to mix a microphone with up to eight karaoke tracks. Efficient power supply design is enabled by an integrated smart energy manager that can limit the audio system’s peak power by interrupting the host processor if the power threshold is reached. For high-end audio systems, a power supply volume control enables energy-efficient high-power performance.

The TAS5548EVM evaluation module costs $99 and comes with the ControlConsole graphical development suite to simplify the evaluation, configuration and debug of audio products. The ControlConsole’s graphical user interface (GUI) enables quick evaluation of all TAS5548 functions, including DRC, programmable EQ, and energy management. The TAS5548 costs $3.68 (1000).

TI, www.ti.com/tas5548s-pr