LM4844 Datasheet, PDF (1/21 Pages) National Semiconductor (TI) – Stereo 1.2W Audio Sub-system with 3D Enhancement

June 2005
LM4844
Stereo 1.2W Audio Sub-system with 3D Enhancement
General Description
The LM4844 is an integrated audio sub-system designed for
stereo cell phone applications. Operating on a 3.3V supply, it
combines a stereo speaker amplifier delivering 495mW per
channel into an 8Ω load and a stereo OCL headphone
amplifier delivering 33mW per channel into a 32Ω load.
It integrates the audio amplifiers, volume control, mixer,
power management control, and National 3D enhancement
all into a single package. In addition, the LM4844 routes and
mixes the stereo and mono inputs into 10 distinct output
modes. The LM4844 is controlled through an I²C compatible
interface.
Boomer audio power amplifiers are designed specifically to
provide high quality output power with a minimal amount of
external components.
The LM4844 is available in a very small 2.5mm x 2.9mm
30-bump micro SMD (TL) package.
Key Specifications
j P_OUT, Stereo BTL, 8Ω, 3.3V,
1% THD+N
j P_OUT HP, 32Ω, 3.3V,
1% THD+N
j Shutdown Current, 3.3V
495mW (typ)
33mW (typ)
0.1µA (typ)
Features
n Stereo speaker amplifier
n Stereo OCL headphone amplifier
n Independent Left, Right, and Mono volume controls
n National 3D enhancement
n I²C compatible interface
n Ultra low shutdown current
n Click and Pop Suppression circuit
n 10 distinct output modes
Applications
n Cell Phones
n PDAs
n Portable Gaming Devices
n Internet Appliances
n Portable DVD, CD, AAC, and MP3 Players
Block Diagram
20153531
FIGURE 1. Audio Sub-system Block Diagram
Boomer^® is a registered trademark of National Semiconductor Corporation.
© 2005 National Semiconductor Corporation DS201535
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