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.
LM4780/81/82
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 (°Ke) (SPiKeTM) 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.
Pricing and Availability
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.
