Contact: Keithley Instruments, Inc.
28775 Aurora Road
Cleveland, Ohio 44139

Keithley Signs Agreement to Partner with Modelithics

Cleveland, Ohio - May 29, 2003 - Keithley Instruments, Inc. (NYSE: KEI) has entered into a collaborative agreement with Modelithics, Inc. of Temple Terrace, Florida. The two companies will share information and work together to create more efficient software modeling techniques used to design advanced RF (radio frequency) semiconductor devices.

Modelithics ( specializes in RF and microwave device modeling and characterization. Keithley is a leading supplier of semiconductor parametric testing and characterization instruments ( The two companies will combine resources to create advanced methods for using I-V and C-V data for more efficient device modeling and circuit design.

"The ability to combine Modelithics' demonstrated expertise in RF modeling with our RF measurement capability presents a powerful tool for our customers," explained Keithley chairman, president and CEO Joseph P. Keithley. "Many of those customers are currently expanding their use of RF modeling as they seek to reduce the number of iterations required during the design phase. The advanced techniques that our two companies create through this collaboration will make both of us more valuable resources for our customers. In addition, this raises Keithley's profile among the design engineers within this segment, beyond the production and manufacturing engineers we have been serving to date."

"Partnering with Keithley as one of the semiconductor industry's premier measurement technology companies goes a long way toward improving our presence in this market," added Modelithics' president, Larry Dunleavy. "We each will be more successful collaborating than if we had attempted to serve our core customers alone."

The collaboration between Keithley and Modelithics is an extension of earlier Keithley partnerships announced with other semiconductor companies, including Novellus, Anritsu, and Suss Microtec. "These types of partnerships are becoming more commonplace as the industry recognizes that no single company can provide complete solutions to customers. Vendors are forming these alliances rather than force their customers to identify and build these linkages on their own," Keithley explained.

About Keithley Instruments, Inc. Keithley Instruments, Inc. provides optical and electrical measurement solutions from DC to RF (radio frequency) to the wireless, semiconductor, optoelectronics, and other electronics manufacturing industries. Engineers and scientists around the world use Keithley's advanced hardware and software for process monitoring, production test, and basic research.

About Modelithics. Modelithics, Inc. provides highest quality, RF/microwave/mm-wave characterization and modeling products. The company offers a broad array of measurement services, including S-parameters, noise parameters, and source/load-pull. It also specializes in equivalent circuit and black-box models for linear and non-linear devices that can be inserted into most microwave computer-aided-engineering (CAE) software tools currently on the market. The company's founders, Drs. Lawrence Dunleavy and Thomas Weller, have more than 30 years of combined experience in microwave characterization and modeling. Modelithics' current customers include component manufacturers and product designers in the wireless/microwave and optical technology sectors.

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