NATIONAL SEMICONDUCTOR'S LATEST BOOMER AUDIO AMPLIFIER PROVIDES SUPERIOR AUDIO AMPLIFICATION AND COST-EFFECTIVE DC VOLUME CONTROL 

LM4865 Enables Loud, Clear Audio for Cellular Phones

June 28, 1999 - National Semiconductor Corporation? (NYSE: NSM) today announced the LM4865, a 1W mono-bridged audio power amplifier with DC volume control. Part of the company's popular Boomer? audio amplifier product family that delivers design simplicity and quality sound, the new LM4865 provides superior audio amplification to enhance cellular phones. Manufacturers can use the LM4865 to differentiate their products from the competition by leveraging its robust feature set and cost-effective integration of a DC volume control. 

Cellular phones are now designed with increased functionality to play music, perform conference calling and run sophisticated video games. These advanced features require a device that enables exceptional audio amplification and maintains low power for longer battery life. The LM4865 meets these requirements with a power supply from 5.5V down to 2.7V, which is ideal for cellular phones. Power out with an 8-ohm load is 1W with less than 10 percent total harmonic distortion (THD). The component extends the operating time of battery-powered cell phones by consuming as little as 0.7mA (typical) in shutdown/sleep mode.

For cellular phones with a headphone jack, the LM4865 has a headphone mode feature that can turn off the speakers when the headphone is plugged in. This is an added convenience for the user, as well as a power-saving measure. Additionally, a minimal number of external components, combined with the product's small footprint, greatly simplifies overall system design, saves board space and lowers manufacturing costs. 

"We developed the LM4865 to address specific needs for increased performance and functionality that are driving developments in the cellular phone market," said Ken Boyce, marketing manager for the audio product line. "No other audio amplifiers provide the combination of features, audio quality and cost effectiveness that Boomer audio amplifiers do."

Packaging for the Smallest Space Requirements
The LM4865 offers designers a low voltage audio amplifier solution in a small package without sacrificing output power or audio quality. The LM4865's MSOP package occupies only half the board space of a standard small outline (SO) package, making the audio amplifier ideal for small cell phones. The device is also available in a standard SO-8 package. In addition, for smaller designs that are heat sensitive, an internal thermal shut down mechanism protects the LM4865 from overheating.

Pricing and Availability
Samples of the LM4865 are currently available. The LM4865MM in a MSOP-8 package is priced at $0.70 each in quantities of 1,000. The LM4865M in the SO-8 package is priced at $0.70 each in quantities of 1,000. For more information on the LM4865, please visit http://www.national.com/pf/LM/LM4865.html.

About National
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 has annual revenues of $2 billion and 11,500 employees worldwide. Additional company and product information is available on the World Wide Web at www.national.com.