Santa Clara, CA – March 10, 2004 – National Semiconductor Corporation announced three new stereo audio amplifiers in its Overture line of products for home stereo systems. National's newest audio amplifiers feature quiet fade-in/fade-out mute mode circuitry that gradually brings the sound up or down. These “easy on the ears” transitions enhance the listening experience in compact stereos, high-definition televisions (HDTVs), 5.1 surround sound systems and other consumer electronic equipment.
National's LM4780 is a stereo audio amplifier capable of delivering 60W per channel of continuous average output power. The LM4781 is a three channel audio amplifier capable of delivering 35W per channel of continuous average output power into an 8 Ohm load, and the LM4782 is a three channel audio channel capable of delivering 25W per channel of continuous average output power into an 8 Ohm load, all with less than 0.5% total harmonic distortion plus noise (THD+N) from 20Hz ” 20kHz.
The LM4780/81/82 audio amplifiers are fully protected by National's self-peak instantaneous temperature (degrees Kelvin) (SPiKe) protection circuitry. SPiKe circuitry provides a dynamically optimized safe operating area. SPiKe protection completely safeguards the LM4780/81/82 outputs against over-voltage, under-voltage, overloads, shorts to the supply or ground, thermal runaway and instantaneous temperature peaks. The advanced protection features of the LM4780/81/82 audio amplifiers are unique in the field of discrete and hybrid amplifiers. The LM4780/81/82 audio amplifiers can easily be configured for bridge or parallel operation for higher power and bi-amp solutions. All three audio amplifiers feature independent, smooth fade-in/out mute. In addition, the LM4782 has a power-conserving stand-by mode. The mute and stand-by modes can be controlled by external logic signals.
With a leading market share in audio amplifiers for cellular handsets, National delivers audio solutions to nearly every handset maker in the world. In addition to providing chips for cellular handsets, National manufactures Class AB and Class D audio amplifiers for consumer stereo and home theater systems, and headphone and speaker drivers in notebook computers and portable audio devices.
The LM4780 is available now in 27-lead TO-220 packaging and is priced at $3.25. The LM4781 is available now in TO-220 packaging and is priced at $3.25. The LM4782 is available now in TO-220 packaging and is priced at $2.75. All prices are for 1,000-unit quantities.