NATIONAL SEMICONDUCTOR ANNOUNCES FIRST TRUE ?0.33?C HIGH-ACCURACY DIGITAL TEMPERATURE SENSOR ON THE MARKET

LM92 Provides Better Than ?0.33?C to ?1.5?C Accuracy Over the Full Temperature Range (-25?C to 150?C)

March 13, 2000 - National Semiconductor Corporation (NYSE:NSM) today announced the LM92, the latest addition to its digital temperature sensor family. The LM92 is a ?0.33?C high-accuracy digital temperature sensor with thermal window comparator. The thermal window comparator and two-wire interface makes designing temperature-control systems easy. The host can program both the upper and lower limits of the window, as well as the critical-temperature shutdown limit, via a two-wire serial bus interface.

With a 12-bit + sign analog-to-digital converter, which has 0.0625?C resolution, the LM92 achieves better than ?0.33?C accuracy at 30?C. Over the temperature range, the accuracy is better than:

?	?0.5?C, 	+10?C to +50?C
?	?1.0?C, 	-10?C to + 85?C
?	?1.5?C, 	-25?C to +150?C

"The LM92 is ideal for high-accuracy applications such as heating, ventilating, air conditioning, medical, test equipment, automotive, basestations and a host of other applications which typically require higher accuracies over limited temperature ranges," said Deborah Brown, technical marketing manager for National's data conversion group. "Before the LM92, analog temperature sensors or thermistors were the only solutions available to achieve such high accuracy. These solutions require additional linearization circuitry and calibration that add cost. Also, the test approach necessary to provide high accuracy analog solutions impacts volume production. With enhanced test methodologies, the LM92 is able to reliably achieve its accuracy in high volume."

A key feature of the LM92 is its excellent linearity of ?0.5?C maximum. Other features included are compatibility with both I²C? Bus and SMBus, and the timeout feature to prevent serial bus lock-up. Programmable hysteresis and a fault queue of up to four faults are provided to prevent false tripping when used in noisy environments. As many as four sensors can use the same serial bus. The device's supply-voltage range is 2.7V to 5.5V.

Pricing and Availability
Available now, the LM92 costs $2.05 each in 1000 unit quantities and is packaged in a space-saving 8-lead SOP. For more information, please visit National's World Wide Web site at http://www.national.com/pf/LM/LM92.html.

About National Semiconductor
National Semiconductor provides system-on-a-chip solutions for the information age. Combining real-world analog and state-of the-art digital technology, the company's chips lead many sectors of the personal computer, communications, and consumer markets. With headquarters in Santa Clara, California, National reported sales of $2 billion for its last fiscal year and has about 10,500 employees worldwide. Additional company and product information is available on the World Wide Web at www.national.com.