Exar Debuts Industry's First Standards Compliant Single-Chip Fully Integrated Jitter Attenuator for DS3/E3 Networking and Transmission Applications.
Business Editors/High Tech Writers
FREMONT, Calif.--(BUSINESS WIRE)--Feb. 7, 2000
Breakthrough Device Reduces Component Count and System Costs
EXAR Corporation (Nasdaq: EXAR) today announced the industry's first standards compliant jitter attenuator at·ten·u·a·tor
A device that attenuates an electrical signal.
Noun 1. attenuator - an electrical device for attenuating the strength of an electrical signal device for E3 and DS3 networking and transmission applications.
The XRT XRT
A symbol used specifically upon the consolidated tape to indicate a security trading ex-rights.
Typically, a stock will depreciate in price immediately after rights offering expires. 71D00 performs all the essential functions needed to meet the jitter attenuation Loss of signal power in a transmission.
The reduction in level of a transmitted quantity as a function of a parameter, usually distance. It is applied mainly to acoustic or electromagnetic waves and is expressed as the ratio of power densities. requirements outlined in the Bellcore GR-499, and European Telecommunication Standards Institute's (ETSI (European Telecommunications Standards Institute, Sophia Antipolis technical park, Nice, France, www.etsi.org) A non-profit membership organization founded in 1988, dedicated to standardizing information and communication technologies (ICT) throughout Europe. ) TBR-24 standards. Compliance is crucial to ensure compatibility in a wide range of worldwide networking environments.
The XRT71D00 performs the work currently required by as many as four or five separate discrete chips. This enables accelerated development of full standards compliant DS3/E3 products. The XRT71D00 is ideal for many DS3/E3 transmission applications including digital multiplex and de-multiplex equipment, DS3/E3 line interface units, fiber optic and microwave radio terminals, and Pulse Code Modulation pulse code modulation: see modulation.
(data) Pulse Code Modulation - (PCM) A method by which an audio signal is represented as digital data. (PCM (1) See phase change memory.
(2) (Plug Compatible Manufacturer) An organization that makes a computer or electronic device that is compatible with an existing machine. ) test equipment.
&uot;With the industry's first jitter attenuator device, Exar now has the most robust product portfolio of silicon solutions for DS3/E3 physical interface applications,&uot; said Dr. Roubik Gregorian, senior vice president, and general manager of Communications division, Exar Corporation. &uot;This product represents the completion of another step in our larger strategic plans to offer the industry the most innovative and comprehensive solutions for Wide Area Networks (WAN).&uot;
Why is Jitter Important?
The phenomenon of jitter has long plagued networking and transmission designs. Jitter is caused by many factors: cross-talk noise, imperfect timing recovery circuitry, or line interface/signal distortion. Typical WAN environments contain many pieces of equipment (nodes). At each point of connection (node), jitter can increase, and as a result new errors can be introduced into data transmitted from one end of the system to the other causing data to be received with errors. In order to insure the reliable reception of data, there is a need to reduce the amount of jitter added to the transmitted signal.
How it Works
The XRT71D00 consists of three functional blocks, each playing a crucial role in jitter attenuation. The device is composed of the timing control block, jitter attenuator Phase Lock Loop (PLL PLL - phase-locked loop ), and the two-channel 16/32-bit First in First Out (FIFO (First In First Out) A storage method that retrieves the item stored for the longest time. Contrast with LIFO. See traffic engineering methods.
FIFO - first-in first-out ). The XRT71D00 accepts recovered clock and data signals from the Line Interface Unit (LIU). The data is then clocked into the FIFO, while in parallel the clock signal is also input to the PLL. The jitter attenuator PLL will track and regenerate the recovered clock signal with considerably less jitter. This &uot;smoothed&uot; clock signal will then be routed to the terminal equipment. The &uot;smoothed&uot; clock will also be used to clock the recovered data out of the z-channel FIFO. This permits the output data to be aligned with the &uot;smoothed&uot; clock signal.
The jitter attenuator device functions at the E3 (34.368 Mega bits per second), and DS3 (44.736 Mega bits per second) data rates. These rates are typically found in DS3/E3 line interface units, multiplex and de-multiplex and other devices where high-speed Internet traffic is processed. The XRT71D00 operates with either 5V or 3.3V power supply with 5V input tolerance and supports -40 to 85 degree C temperature range. The XRT71D00 is compliant with ETSI TBR-24, ITU-T See ITU.
ITU-T - International Telecommunications Union G.751, 752 and 755, as well as the Bellcore GR-499-CORE Category I and Category II equipment, and supports both software and hardware modes for configuration and control.
Limited samples of the XRT71D00 will be available in February, 2000. The XRT71D00 can be packaged in two varieties: 24-pin SOIC (Small Outline IC) A small-dimension, plastic, rectangular, surface mount chip package that uses gull-wing pins extending outward. See gull-wing lead, SOJ and chip package. , or 32-pin TQFP See QFP. at the industrial temperature range of -40 to 85 degree C. The XRT71D00 is priced at $35.00 in 1,000 piece quantities.
Exar Corporation designs, develops and markets innovative, system-oriented mixed-signal integrated circuits for high-speed broadband communications and data acquisition markets. The company, based in Fremont, had fiscal 1999 revenues of $71.9 million and employs approximately 275 people worldwide.