LM4863
Dual 2.2W Audio Amplifier Plus Stereo Headphone
Function
General Description
The LM4863 is a dual bridge-connected audio power ampli-
fier which, when connected to a 5V supply, will deliver 2.2W
toa4Ωload (Note 1) or 2.5W to a 3Ω load (Note 2)with less
than 1.0
%
THD+N. In addition, the headphone input pin al-
lows the amplifiers to operate in single-ended mode to drive
stereo headphones.
Boomer audio power amplifiers were designed specifically to
provide high quality output power from a surface mount
package while requiring few external components. To sim-
plify audio system design, the LM4863 combines dual bridge
speaker amplifiers and stereo headphone amplifiers on one
chip.
The LM4863 features an externally controlled, low-power
consumption shutdown mode, a stereo headphone amplifier
mode, and thermal shutdown protection. It also utilizes cir-
cuitry to reduce “clicks and pops” during device turn-on.
Note 1: An LM4863MTE which has been properly mounted to the circuit
board will deliver 2.2W into 4Ω. The other package options for the LM4863
will deliver 1.1W into 8Ω. See the Application Information section for
LM4863MTE usage information.
Note 2: An LM4863MTE which has been properly mounted to the circuit
board and forced-air cooled will deliver 2.5W into 3Ω.
Key Specifications
n P
O
at 1
%
THD+N
into 3Ω (LM4863MTE) 2.5W(typ)
into 4Ω (LM4863MTE) 2.2W(typ)
into 8Ω (LM4863) 1.1W(typ)
n Single-ended mode - THD+N
at 75mW into 32Ω
0.5
%
(max)
n Shutdown current 0.7µA(typ)
Features
n Stereo headphone amplifier mode
n “Click and pop” suppression circuitry
n Unity-gain stable
n Thermal shutdown protection circuitry
n Exposed-DAP TSSOP, TSSOP, SOIC and DIP
packaging available
Applications
n Multimedia monitors
n Portable and desktop computers
n Portable televisions
Typical Application
Boomer
®
is a registered trademark of National Semiconductor Corporation.
DS012881-1
*
Refer to the section Proper Selection of External Components, for a detailed discussion of C
B
size.
FIGURE 1. Typical Audio Amplifier Application Circuit
October 1999
LM4863 Dual 2.2W Audio Amplifier Plus Stereo Headphone Function
© 1999 National Semiconductor Corporation DS012881 www.national.com
