Crystal offers reference design, wavetable device

Electronic News, June 26, 1995 by Anthony Cataldo

AUSTIN, TEXAS--Addressing calls for high-quality audio technology on PCs, Cirrus Logic's Crystal Semiconductor subsidiary unveiled a Plug-and-Play audio adapter board reference design and a wavetable music synthesizer device.

Touted as the "only" Plug-and-Play audio solution on the market, the CRD4232-2 audio/telephony reference design provides a model for CD-quality digital audio, industry standard music synthesis and V.32bis/V.17 subsystems. The reference design is based on Crystal's CS4232 Plug-and-Play audio codec and the Cirrus CL-MD 1414 chipset for data, facsimile and voice communications.

Adding audio as a standard feature to the PC is being driven by the proliferation of low-cost semiconductor hardware such as 486 and Pentium microprocessors, hard drives exceeding 300 MBytes, CD-ROM drives and high-performance graphics subsystems.

New software applications that leverage 16-bit sound--galvanized by Microsoft's Direct-Sound application programming interface--are also becoming more prevalent along with burgeoning technology such as 3-D audio and Internet voice communications, said David Konetski, Crystal's technical marketing specialist.

"The enabling technology is here," Mr. Konetski said. "Home users are the fastest growing market segment by far. They all require high quality audio if they want to get their money's worth."

Multimedia audio unit shipments are expected to jump from nearly 20,000 units in 1994 to more than 40,000 in 1995. Additionally, the total number of audio adapter cards will begin to gradually decline from a peak of more than 20,000 by the end of 1995, fueled by the penetration of audio onto the motherboard, according to Crystal.

At the heart of the reference design is the CS4232 a games-compatible, Plug-and-Play audio codec that provides Sound Blaster compatibility, MPU 401 and MIDI ports, synthesizer support, a CD-ROM and joystick interface, and programmable power management.

Mr. Konetski maintained that the rules governing relationships between suppliers and OEMs have changed, which has led Crystal to strengthen its systems engineering department over the last four years to include services such as custom software and hardware support.

"You can't just give a chip and a data sheet to an OEM anymore," Mr. Konetski said.

Additionally, the company introduced a digital signal processor (DSP)-based CS9233 wavetable and FM synthesis device, which can be ported onto a CRD4232-2 board via a daughtercard.

The 18-bit audio part--a 32-note, superscalar device operating at 31.25kHz--contains a glueless interface to ROM-based wave synthesis samples and hooks to an effects processor. It is also compatible with General MIDI and General Roland Synthesizer as well as music synthesis supported by Windows Sound System.

Supporting devices for a wavetable solution based on the CS9233 would include a CS4112 ROM, a CS4331 DAC, 256-Kbits of SRAM, 1-Mbit of ROM or EPROM, according to the company.

The CS9233 also uses Crystal's homegrown FM synthesis technology, which has been the subject of several legal disputes initiated by key patent holder Yamaha. Currently, Yamaha is trying to prevent ESS Technology from selling audio parts that ESS claims are immune from patent infringement (EN, May 22).

Crystal said its FM synthesis technology side-steps the Yamaha patents. "We are carefully engineering the technology and have manufacturing patents of our own," Mr. Konetski said. "We have probably spent more legal hours developing the technology than engineering hours."

The CS9233 wavetable synthesis device, packaged in a 144-pin TQFP, is available now in volume quantities for $14.20 in 10,000-unit quantities.

In a separate development, Crystal said it will work with its OEMs to promulgate an Internet telephone technology licensed from Israel-based Vocaltec Inc. The licensing agreement with Vocaltec was billed as a way to nurture audio technology requiring hardware support.

Vocaltec, which uses a proprietary algorithm enabling full-duplex voice transmissions over the Internet, will take advantage of Cirrus Logic's distribution channels and OEM base while Cirrus and Crystal hope the new technology will help spur sales of the CS4232 codec and CL-MD 1414 modem chipset, Mr. Konetski said.

"Right now it's more of a wonderment and it does require a certain installed base to be efficient," Mr. Konetski said. "It gives us an advantage because our OEMs are able to offer a unique technology while we provide the testing and supply."

The phone software package also will be bundled with the CRD4232-2 reference design, which is available now.