STMicroelectronics Adds Audio Processor with Highly-Efficient Audio Codec to All-Digital Sound Terminal™ Family

With its very low power consumption, excellent processing capability at up to 75MHz, and high audio quality, the STA331 can be used for both portable and stationary applications, with the same chip being used across a range of products such as set-top boxes (STBs), home audio systems, mini and micro component systems, and wireless speakers and headphones. When combined with the STA510F – a new digital power stage designed specifically for FFX drivers – the STA331 can drive audio power up to 100W per channel.

The STA331’s analog and digital audio peripherals make it an ideal and flexible solution for mid-range sound-processing applications, where product differentiation is critical. The code runs from the embedded RAM, uploaded from external serial Flash memory, and the whole set of audio parameters and functions can be controlled via an I2C interface, or through a customizable GPIO interface for standalone operation. Moreover, the widely used ARM7TDMI core allows fast porting of the third-party audio effects that are available for ARM processors.

The STA331 embeds a stereo ADC (analog to digital converter), the FFX PWM (pulse width modulation) modulator, and a powerful bridge, in a single package, along with multi-standard digital connectivity and a three-way input selector. Full multiplexing of multiple audio sources is possible.

A complete library of algorithms has been developed to improve the listening experience of both musical and video content. The library includes digital audio processing, such as ST’s proprietary Tones Control, WideSurround, StereoEnhancer, intelligent volume control (MDCR), enhanced listening modes (voice and midnight modes), noise reduction and echo cancellation, and loudspeaker and cabinet compensation EQ. Compressed audio algorithm decoders, in addition to common third-party algorithms, are available upon request.

“The STA331 is the most advanced implementation of the Sound Terminal concept so far,” said Andrea Onetti, General Manager of ST’s Audio Division. “FFX-based products already provide users with a seamless audio link from both analog and digital signals, and from different sources, including wireless and MEMS-based applications, to the loudspeaker. The addition of the ARM7 core in the STA331 means that ST is the first silicon manufacturer to offer a digital modulator flexible enough to be used across the whole range of consumer audio products.”