Dual Audio Amplifiers Drive Down Cost Per Watt in Mini-Component Stereos and TV Sound Systems

June 24, 1997 -- National Semiconductor Corporation® today announced availability of stereo audio amplifiers that deliver 11W per channel into 4-ohm speakers and 7W per channel into 8-ohm loads from a 24V supply at 10% THD (total harmonic distortion). The LM4752 and LM4755 give designers of mini-component systems and compact TVs the lowest cost-per-watt of any comparable part in the industry.

"In a highly competitive market, our OEM customers now expect to pay only pennies per watt for audio amplification, and we made that our target in designing these devices," said Steve Kaufman, strategic marketing manager for National's audio group. "On examination of all the criteria evaluated in selecting a power amp for compact stereo mini-components, these parts meet or exceed competitive amplifiers in power and price. They also require the fewest number of external ICs," he added.

The key difference between the two devices: The LM4755 includes a built-in mute feature, while muting the LM4752 requires a few external components.

Both parts are optimized for single-supply operation at the 20V to 24V range, with maximum headroom allowed under operational range from 9V to 32V. With gain internally set at 34dB, the number of external components required is reduced by as much as 50%. Both operate through the full temperature range of -20C to +85C.

Price and Availability
The LM4752 is now available in a 7-lead TO220 package. In quantities of 1000, the LM4752T is priced at $1.90 each. The LM4755T is offered in a 9-lead TO220 package and is priced at $2.10 in 1000s.

For more information on the LM4752 or LM4755, visit our website at http://www.national.com/pf/LM/LM4752.html or http://www.national.com/pf/LM/LM4755.html.

National Semiconductor Corporation, a Fortune 500 company, produces system on a chip silicon solutions for the information highway, based on its leadership in analog and mixed signal technologies. National is headquartered in Santa Clara, California, and focuses on the communications, personal systems and consumer markets. National has annual sales of approximately $2 billion and 12,000 employees worldwide. Additional company and product information is available on the World Wide Web at www.national.com.