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Semtech Serves Up Latest Low-Capacitance RailClamp® Surge Protection Device Optimized for ADSL and Other High-Speed Applications

Camarillo, California - August 19, 2002

Semtech Corp. (Nasdaq: SMTC), a leading supplier of analog and mixed-signal semiconductors for communications, portable devices, computers, and industrial equipment, today announced the SR70, the newest member of the RailClamp® family of low capacitance, surge-rated TVS protection arrays. The SR70 is designed to protect commercial broadband ADSL (asymmetric digital subscriber line) line-driver chipsets from high-energy transients sources including electrostatic discharge (ESD), electrical fast transients (EFT), and lightning. Recognized as the industry’s most robust, cost-effective commercial protection solution available for ADSL, the device has been specifically identified for protection of ADSL line drivers in the latest reference designs from leading ADSL chipset manufacturers.

This tiny protection device shunts damaging voltage surges away from sensitive low-voltage integrated circuits, such as communications line drivers, microcontrollers, digital signal processors, and microprocessors. Although specifically intended for ADSL, the SR70 is also ideally suited for a wide range of other protection applications, such as serial I²C microprocessor buses, video interfaces, telecommunications T1/E1/ISDN interfaces, portable electronics, WAN/LAN equipment, and many other high-speed signal interfaces.

Unlike other commercial protection schemes, Semtech’s TVS array provides superior and reliable high surge-handling capability, combined with very low capacitance (5 picoFarads typical), fast transient response time, and very low clamping voltages. The device’s low capacitance enables designers to fully maintain the integrity of high-speed signals. The SR70 also meets or exceeds all applicable voltage immunity standards, including IEC (International Electrotechnical Commission) specifications for ESD, EFT, and lightning.

Packaged in a low-profile SOT-143 package, one SR70 device is designed to protect one line pair. The maximum clamping voltage seen by protected circuitry during a transient event is held to one diode drop above the SR70’s reference voltage input, which is typically connected to the protected device’s supply voltage.

"ADSL is delivering on the promise of broadband digital service to the home," said Semtech’s Director of Protection Products, Tom Dugan. "Unfortunately, the ADSL modem chipsets used to drive signals at both ends of the copper loop are extremely sensitive to damage from high-energy transients, which commonly occur on ADSL lines . Conventional protection methods such as rectifiers are unreliable for high-energy events such as lightning or ESD. The SR70 fully meets our customer’s most stringent requirements of low capacitance and high surge capability, along with the ability to handle multiple transient events without damage or degradation," added Dugan.

Key Features of the SR70

• Low capacitance (5pF typical) to protect lines without degradation to high speed signals
• Very low clamping voltage—one diode drop above the reference voltage input
• ESD protection to IEC 61000-4-2, Level 4 (8kV contact, 15KV air); EFT protection to IEC 61000-4-4 40A (5/50ns); lightning protection to IEC 61000-4-5 1kV, 24A (8/20us)
• UL 497B listed device integrates four surge-rated diodes to protect one pair of wires
• Low profile, space-saving JEDEC SOT-143 package

Pricing and Availability

The SR70 in a SOT-143 package is now available in sample quantities on tape and reel packaging, with volume production scheduled for September 2002. Pricing is $0.35 per unit in lots of 10,000 or more. Semtech offers comprehensive support to customers integrating the SR70 devices into their system designs. Datasheets are available at www.semtech.com.

About Semtech

Semtech Corporation is a leading supplier of high-quality analog and mixed-signal Ics for power management, over-voltage and transient protection, human interface devices & system management, test & measurement applications, and advanced communications. Publicly traded since 1967, Semtech is listed on the NASDAQ National Market under the symbol SMTC. For more information, contact Semtech Corporation at 200 Flynn Road, Camarillo, CA. 93012-8790; phone (805) 498-2111; email to info@semtech.com; or visit its Web site at www.semtech.com.

Semtech, the Semtech logo, and RailClamp are marks of Semtech Corporation.

Press Contact

Terry Sears, Marketing Communications Manager, Telephone: 805.498.2111