Cicada Semiconductor Sets New Industry Standard with First and Only Multichannel DSP-Based Line Interface Units for T3/E3/STS-1 Applications.

Business Editors & High-Tech Writers

NetWorld+Interop 2002 Las Vegas 

Booth No. 3051

AUSTIN, Texas & LAS VEGAS, Nev.--(BUSINESS WIRE)--May 7, 2002

High Density LIUs with Integrated Jitter Attenuators Drastically

Reduce Power Consumption and Feature Advanced Performance

with Adaptability to Real-World Applications

(Networld+Interop Booth #3051) Cicada Semiconductor Corporation, the leading developer of DSP and mixed-signal integrated circuits (ICs) that enable broadband communications within Local, Wide, and Storage Area Networks, announced today the first two products in its new family of DSP-based, multichannel Line Interface Units (LIUs) intended for DS3 (T3), E3 and STS-1 applications.

The CIS7516, six channel and CIS7518, eight channel LIUs incorporate a Cicada-distinctive DSP approach to LIU design that provides substantially improved performance and rich feature integration, while consuming 40-50 percent less power than all competitive products. Power consumption and restricted board space have been increasing concerns among design engineers as more features are incorporated into communication and data networking systems demanding higher integration and low power consumption. Cicada's advanced features include jitter attenuation in both transmit and receive paths, on-chip multirate clock generation, and greater adaptability to system-level constraints, which ensure quick design-in and compatibility with prior generations of existing equipment.

"The CIS7516 and CIS7518 mark significant advances in LIU technology compared to the old analog approach to equalization," said Cicada CEO Nick van Bavel. "Not only has Cicada substantially advanced LIU performance, but we have included features and functionality normally implemented in surrounding support circuitry, while dramatically reducing power consumption. As the market continues to demand higher port densities, our new product family allows designers to greatly reduce system costs and simplify their design task."

LIUs provide the essential physical layer functionality for T3, E3, and STS-1 transmission systems such as multi-access multiplexors, routers, switches, and concentrators that are used in telecom infrastructure equipment. The application of DSP technology to line interface circuits provides breakthrough performance, including very robust data recovery in the presence of channel impairments such as jitter, noise and crosstalk commonly found in real-world environments. DSP based design uses algorithms that are immune to such things as temperature, so that the LIU overcomes the unpredictability and manufacturing issues associated with analog design techniques. Cicada's DSP approach extends both the reach and the reliability of systems utilizing the chip. In fact, in laboratory testing, the Cicada LIUs have accurately recovered signals transmitted over more than 1500 feet of cable, far exceeding the industry requirement of 900 feet.

Key Differentiating Features of the CIS7516 and CIS7518

Cicada's DSP-based receiver optimizes the device's ability to equalize and adapt to cable and system environment while providing much greater noise rejection. This significantly improves the range of adaptability and tolerance to channel impairments such as noise, crosstalk, and sub-optimal cabling and system configurations. Conversely, the analog equalizers found in competitive products have a very limited ability to equalize, as they are designed for coaxial cable models only and cannot adapt to the real-world environments where layout is not optimal and noise couples into the system from various sources.

Three key features that are unique to Cicada LIUs are: jitter attenuation in both the transmit and receive signal paths, output pulse shape adjustability, and a multi-rate capability that allows the channels to simultaneously run a mix of data rates from a single, telecom-standard reference clock, thereby reducing system cost and complexity.

Cicada also includes the ability to control the LIUs through dedicated pins or via a serial or parallel microcontroller interface. Under software control, a Channel Management System allows the system to easily and efficiently determine the status, and control the channels of the device. This unique feature eliminates much of the processor overhead required to manage the operation of the LIU. Under processor control, the LIU also features the ability to generate and receive data patterns to facilitate testing of an installed system.

Other Key Technical Features Include:

Tx and Rx jitter attenuation -- To eliminate the problem of output jitter for many systems manufacturers, Cicada provides both transmit and receive jitter attenuation, and offers a very high-performance circuit. This ensures a high-quality receive clock for loop-timed high-speed circuits. FIFO depths are user selectable. The transmit jitter attenuator is designed to absorb the gaps that result from bit destuffing and pointer adjustments that occur in SONET applications, while achieving extremely low intrinsic jitter.

Internal generation of required frequency reference -- All competitive LIUs require line-rate frequency references. Cicada's approach of generating the required frequency reference from any number of frequencies generally available in telecom applications will often save the customer from having to provide accurate and thereby expensive frequency references, particularly where multiple rate operation is required.

DSP-based clock recovery circuit -- Provides receive jitter tolerance that far exceeds that of any competitor.

No false lock -- Unlike analog equalizers and PLLs that often falsely lock to noise when a signal is not present.

Adjustable output pulse shape -- Allows fine adjustment of output pulse shape to account for board level imperfections and thus ensure that the resulting system can meet transmit pulse templates.

Compliance with all applicable specifications -- Including: ITU-T G.703, GR-499-CORE, GR-253-CORE, T1-102 and T1-404.

Power supplies -- 3.3V and 1.5V (or 1.8V) power supplies, including ability to regulate the 1.5V supply from the 3.3V supply using only a simple external FET transistor.

Pricing and Availability

The CIS7518 is available in a 19mm 256-pin plastic BGA package, and is priced at $112 in OEM quantities; the CIS7516 is available in a 15mm 196-pin plastic BGA package, and is priced at $88 in OEM quantities. Samples and evaluation boards are available now from Cicada. Contact Roger Taylor at [e-mail] for more information.

About Cicada Semiconductor (Booth #3051)

Cicada Semiconductor is a fabless semiconductor company that designs, manufactures, and markets mixed-signal integrated circuits for the communications industry to send information faster and farther over existing copper cabling and system backplanes within Local, Wide and Storage Area Networks. Already recognized among an elite group of world-class digital communications players with a rare combination of digital and analog design experience, Cicada's mission is to be the worldwide leader in the design and development of high performance digital communications ICs. Now in full production with worldwide sales offices, Cicada's current products include two (quad-port and single port) SimpliPHY(tm) Gigabit Ethernet transceivers and the industry's only DSP-based multichannel Line Interface Units (LIUs). For more information, go to www.cicada-semi.com, or call 512/327-3500.