LM4843 Datasheet, PDF (1/19 Pages) National Semiconductor (TI) – Stereo 2W Audio Power Amplifiers with DC Volume Control

July 2002
LM4843
Stereo 2W Audio Power Amplifiers
with DC Volume Control
General Description
The LM4843 is a monolithic integrated circuit that provides
DC volume control, and stereo bridged audio power amplifi-
ers capable of producing 2W into 4Ω (Note 1) with less than
1.0% THD or 2.2W into 3Ω (Note 2) with less than 1.0%
THD.
Boomer^® audio integrated circuits were designed specifically
to provide high quality audio while requiring a minimum
amount of external components. The LM4843 incorporates a
DC volume control with stereo bridged audio power amplifi-
ers making it optimally suited for multimedia monitors, por-
table radios, desktop, and portable computer applications.
The LM4843 features an externally controlled, low-power
consumption shutdown mode, and both a power amplifier
and headphone mute for maximum system flexibility and
performance.
Note 1: When properly mounted to the circuit board, the LM4843MH will
deliver 2W into 4Ω. See the Application Information section for LM4843MH
usage information.
Note 2: LM4843MH that has been properly mounted to the circuit board and
forced-air cooled will deliver 2.2W into 3Ω.
Key Specifications
n P_O at 1% THD+N
n into 3Ω
n into 4Ω
n into 8Ω
n Shutdown current
2.2W (typ)
2.0W (typ)
1.1W (typ)
0.7µA (typ)
Features
n Acoustically Enhanced DC Volume Control Taper
n Stereo bridged power amplifiers
n “Click and pop” suppression circuitry
n Thermal shutdown protection circuitry
Applications
n Portable and Desktop Computers
n Multimedia Monitors
n Portable Radios, PDAs, and Portable TVs
Block Diagram
FIGURE 1. LM4843 Block Diagram
20038389
Boomer^® is a registered trademark of NationalSemiconductor Corporation.
© 2002 National Semiconductor Corporation DS200383
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