Codec, sound controllers key new ADI offerings

Electronic News, April 8, 1996 by Sarah Cohen

Norwood, Mass.--Analog Devices Inc. is rolling out a number of new audio chips this month. Included among them are the ADSP-2181 digital signal processor (DSP) MPEG-1 audio encode/decode codec chip demonstrated a few weeks ago at the CeBit Show in Hannover, Germany; the SSM2163 8-input, audio mixer-on-chip; and the AD185 and AD186 new line of single-chip sound controllers.

The MPEG-1 audio encode/decode codec chip is currently available and priced at $30 each in quantities of 10,000 units. The codec consists of real-time implementation of the ISO/IEC 11172-3 MPEG-1 audio standard on an Analog Device ADSP-2181 digital signal processor (DSP). Because of the high MIPS and on-chip program and data memory of the ADSP-2181, full encode/decode capabilities are contained on this single chip. No additional SRAM is required.

ADI describes the new SSM2163 as a functionally complete, 8-input, audio mixer-on-chip that includes digitally controlled attenuators, an output switching network, shift registers and an address decoder. ADI claims the chip "replaces expensive multichip solutions in computer audio systems and improves audio fidelity."

The SSM2163 accepts eight audio channels, control of volume in 63 1 dB steps, and can mix individual channels to either the right, left, or both. "No additional external components are needed for fully specified operation," the company claims. The SSM2163 is priced at $8 each in quantities of 100, delivery from stock.

Prices range from $15 each for 100,000 units to $25 each for 10,000 units. The company claims these new motherboard and add-in card devices provide the signal processing hardware to complement MMX instruction-based audio and telephony capabilities in PCs. AD1815 is sampling now. AD1816 samples are expected to be available in May.

The AD1815 and AD1816 lines of sound controllers utilize a signal processing technique developed by ADI called continuous-time oversampling. The company said continuous-time oversampling offers low-latency mixing, sample rate conversion and signal stream synchronization of multiple audio, communications and video signals having disparate sample rates.