STMicroelectronics and Infra-Com Develop Wireless Digital Audio Reference Design for High-Quality Home Entertainment Systems
A cost-effective reference design embedding ST and Infra-Com chips featuring non-line-of-sight, high-bit-rate infrared communications and, exploiting the all-digital audio processing and power amplification capabilities of ST's Sound Terminal family
Geneva and NetanyaSTMicroelectronics (STM), a world leader in digital audio ICs, and Infra-Com Ltd., a world leader in short range diffused infrared (DIR) wireless communication ICs, announces a complete reference design for a high-bit-rate wireless audio solution intended for consumer electronic products such as home theater systems, surround-sound and gaming speakers, DTV speakers, as well as portable music and aftermarket accessories. The Drum and Violin designs combine Infra-Com's receiver side IrGate IC with the all-digital class D power amplifier and signal processor from ST's Sound Terminal family, creating a complete high-quality remote audio amplification system.
Audio signals using Infra-Com's IrGate wireless infrared protocol are processed by an IrGT801ADR Modem and Interface IC, which receives data from the infrared sensors in the optical/analog front-end via an LVDS (Low Voltage Differential Signaling) interface and drives the ST's full digital amplifier through an I2S (Inter-IC Sound) serial digital audio interface.
The Drum solution embeds ST's STA326, a fully-digital IC amplifier that is able to deliver 2x60W of audio power into 8 ohm loudspeakers. It provides true hi-fi audio quality, with an uncompressed 24-bit 48kHz PCM (Pulse Code Modulation) wireless link, and almost zero latency for perfect lip-sync. Latency is just 150 microseconds compared to typically more than 7ms for competitive RF-based solutions. Amplifier efficiency is up to 92%among the highest in the marketallowing a compact heatsink and power supply to be used in the overall application. The amplifier enjoys full built-in over-current and over-temperature protection capabilities, and the all-digital audio stream maintains full audio quality and 100dB signal to noise ratio (SNR) and dynamic range.
The Violin solution embeds ST's STA333ML, a fully-digital micro-less IC amplifier that is able to deliver 2x20W without the need of external heatsink. The STA333ML retains the highest digital audio quality without adding software development efforts.
DIR enables optical communication without the need for line-of-sight between the transmitting and receiving nodes. Unlike a direct infrared signalwhich emits light in a narrow beama diffused infrared device floods the room with the infrared emissions and utilizes natural reflections from the ceiling, walls, floor and other surfaces to maintain robust high bit rate communications, unaffected by obstructions or by moving people within the enclosure. The link effectively behaves similarly to a radio signal within its operating space, but with no possibility of being affected by, or generating, radio frequency interference (RFI); it is also insensitive to remote control signals, and cannot be overheard in an adjacent room. Additionally DIR is a worldwide unregulated technology operating at 870nm.
The STA326 single-chip audio system integrates digital audio processing, digital amplifier control and a DDX digital power output stage. It can be configured easily via digital control to operate in one of several different output modes, and offers a full range of processing and equalization options, including up to 4 programmable 28-bit biquads per channel, and bass and treble tone control. The device is one of a range of single-chip and single-package audio products in ST's Sound Terminal family; other amplifiers in the family can be used with the Drum design to satisfy different audio power requirements, from 2x1W up to 2x80W.
"The Drum is the first of a set of complete and easy-to-use turnkey designs for manufacturers of remote audio products, combining high quality amplification with the user convenience of diffused infrared technology," said Andrea Onetti, General Manager of the Audio Division within ST's Home Entertainment and Display Group. "The Drum and similar designs will complement other interfaces such as Bluetooth 2.0 EDR (Enhanced Data Rate), WiFi and UWB (Ultra-WideBand) in the Sound Terminal family, and we look forward to introducing a single-package DIR and digital amplification solution in the future."
The Drum and Violin reference designs are available now as the M2C_IrGT801ADR_STA326 and M2C_IrGT801ADR_STA333ML modules, respectively, for evaluation and product development.