LM4861 1.1W Audio Power Amplifier with Shutdown Mode
May 1997
LM4861
1.1W Audio Power Amplifier with Shutdown Mode
General Description
The LM4861 is a bridge-connected audio power amplifier ca-
pable of delivering 1.1W of continuous average power to an
8Ω load with 1% (THD) using a 5V power supply.
Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components using surface mount packaging. Since
the LM4861 does not require output coupling capacitors,
bootstrap capacitors, or snubber networks, it is optimally
suited for low-power portable systems.
The LM4861 features an externally controlled, low-power
consumption shutdown mode, as well as an internal thermal
shutdown protection mechanism.
The unity-gain stable LM4861 can be configured by external
gain-setting resistors.
Key Specifications
n
THD at 1 kHz at 1W continuous
average output power into 8Ω
n
Output power at 10% THD+N
at 1 kHz into 8Ω
n
Shutdown Current
1.0% (max)
1.5W (typ)
0.6 µA (typ)
Features
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No output coupling capacitors, bootstrap capacitors, or
snubber circuits are necessary
n
Small Outline (SO) packaging
n
Compatible with PC power supplies
n
Thermal shutdown protection circuitry
n
Unity-gain stable
n
External Gain Configuration Capability
Applications
n
n
n
n
Personal computers
Portable consumer products
Self-powered speakers
Toys and games
Typical Application
Connection Diagram
Small Outline Package
DS011986-2
Top View
Order Number LM4861M
See NS Package Number M08A
DS011986-1
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer
®
is a registered trademark of National Semiconductor Corporation.
© 1999 National Semiconductor Corporation
DS011986
www.national.com
NSC [ NATIONAL SEMICONDUCTOR ]
