Crystal Semiconductor Introduces Single-Chip Dolby -- AC-3 -- 5.1 Channel Audio Decoder.

AUSTIN, Texas--(BUSINESS WIRE)--Nov.7, 1996--Crystal Semiconductor Corporation, a wholly owned subsidiary of Cirrus Logic Inc. (Nasdaq: CRUS), today announced the industry's most integrated single-chip Dolby Digital (AC-3) 5.1 Channel Audio Decoder to support Dolby Digital surround applications.

Targeted at AC-3 based audio/visual A/V receiver applications and newly emerging AC-3 applications, the chip's high integration and small footprint will greatly reduce the cost of implementing these solutions. The versatility of the CS4923 is further enhanced by its ability to seamlessly interface with Crystal's recently introduced breakthrough 108dB CS4226 Surround Sound Codec to provide a complete Dolby Digital systems solution.

According to Roger Dressler, technical director of Dolby Laboratories: "The marketplace acceptance of Dolby's leadership Dolby Digital technology has been very satisfying for us. We have received wide acceptance in both our traditional home audio markets as well as the new DVD market, the digital broadcast satellite and most recently the US cable markets. We are happy to have Crystal Semiconductor, a well known supplier of professional audio technology, offer another alternative for providing Dolby Digital surround to the marketplace."

The capabilities provided by the CS4923 are commonly provided by three or more components. Competitive solutions often require a microprocessor to boot the device, an interface ASIC to accommodate limited input ports, an audio PLL and external FIFOs or SRAM to provide adequate data buffering. The CS4923 provides a complete system solution on one chip.

The CS4923 is manufactured using advanced 0.35 micron technology from Cirrus Logic's MiCRUS facility and is packaged in both 44 pin PLCC and 44 pin QFP packages.

The CS4923 provides over 50 MIPS of 24-bit DSP processing, together with custom peripheral hardware, to faithfully reproduce 5.1 channels of AC-3 audio. Support for Dolby Pro Logic decoding is also planned. The CS4923 incorporates an on chip PLL and audio clock manager together with extensive input and output buffering which eliminates the need for external SRAM.

For applications which use microprocessor control, either a dedicated multi-standard serial control port or a parallel 8-bit host port are available. For stand-alone decoding applications an auto- boot mode is available, thus eliminating the need for a host microcontroller.

Will Strauss, president of Forward Concepts, a leading DSP market research firm, noted: "Crystal is a well known industry leader in consumer audio data conversion technology. With the market for consumer audio application specific DSPs growing at a rapid rate, the industry will welcome an AC-3 solution from the audio experts at Crystal. This product should be well received."

The CS4923 has a highly flexible data interface supporting either a serial compressed input format, a parallel data input format or an industry standard S/PDIF (Sony/Philips Digital Interface) input which is IEC-958 compatible. This input flexibility facilitates simultaneous decoding of an incoming AC-3 compressed audio stream while receiving and mixing a separate PCM input stream up to 96Khz.

Further, the CS4923 can transmit the decompressed data output on an S/PDIF (IEC958 compatible) interface or three 2-channel I2S outputs or alternatively through a 6-channel multi-format serial digital audio output.

The introduction of the CS4923 is part of a broader strategy by Cirrus Logic, Inc. to leverage its expertise in the professional audio and PC multimedia marketplace and apply it more broadly to the consumer electronics industry.

Eric Broockman, vice president and general manager of Crystal's Network and Broadcast Products Division said: "The introduction of the CS4923 is targeted at both the Home A/V Receiver marketplace as well as new and emerging applications for Dolby Digital technology. Crystal has been very successful with our 24-bit CS4920A for decoding MPEG audio in Direct Broadcast Satellite receivers in overseas markets. The CS4923 is an outgrowth of this technology. We have listened to our customers and have delivered a great product with superior performance."

The CS4923 is available in both a 44-pin PLCC or a 44-pin QFP (quad flat pack) and will sell for under $15 in large volume. Samples will be available during the first quarter of 1997. Submission for certification by Dolby Laboratories is planned for the first quarter of 1997.

Crystal Semiconductor, located in Austin, Texas, designs, manufactures and markets advanced mixed signal and digital integrated circuit solutions for applications in PC multimedia, wide area communications, LAN communications, consumer audio, DBS Set-Tops, data conversion and signal acquisition markets.

For more information regarding the CS4236 and other products visit our World Wide Web site at http://www.crystal.com or phone [phone] (Fax [phone]) -0-

Note to Editors: Dolby and Pro Logic are registered trademarks of Dolby Laboratories Inc.

CONTACT: Crystal Semiconductor Corporation, Austin

Jo-Dee Benson, 512/912-3823 (editorial)

Terry Ritchie, 512/912-3733 (reader)