Santa Clara, Calif. National Semiconductor Corp. unveiled two Boomer audio amps for cellular phones and portable applications that are said to provide outstanding sound quality and high integration.
National's LM4845 audio subsystem contains a mono amplifier and stereo headphone amplifier. The mono amp delivers 500 mW of power into a mono 8Ω bridge-tied load with one percent total harmonic distortion plus noise (THD+N)
from a 3.3-V power supply. The stereo headphone amplifier delivers 25 mW per
channel of continuous average power into a stereo 32-Ω load with one percent
THD+N from a 3.3-V power supply.
The LM4888 is a dual bridge-connected audio power amplifier which, when
connected to a 5-V supply, will deliver 2.1 W to a 4Ω load or 2.4 W to a 3Ω load with less than 1.0 percent THD+N.
A user-selectable 3D enhancement mode provides enhanced stereo imaging. The amplifier also has two separate headphone enable inputs, each having different logic level thresholds. To simplify audio system design, the LM4888 combines dual bridge speaker amplifiers and
stereo headphone amplifiers on one chip.
“As today's portable devices get smaller and smaller, National's LM4845 and LM4888 provide the integration that makes it possible to deliver additional features, such as camera phones with audio, MP3 players and FM radios, in a compact package,” said
Mike Polacek, vice president of National Semiconductor's Audio group.
Click here to explore audio amplifier solutions on WEBENCH: www.webench.national.com.
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Available now in a 25-bump micro SMD package, the LM4845 is priced at $2.50 and
the LM4888 is available in a 25-lead LLP package and is priced at $1.50, both
in 1,000-unit quantities. Click here for the LM4845 data sheet.Click here for the LM4888 data sheet.
National Semiconductor Corp. , 1-800-272-9959, www.National.com.