
LM4913
2W Monaural, 90mW Stereo Headphone Audio Amplifier
General Description
The unity-gain stable LM4913 is both a mono differential
output (for bridge-tied loads, or BTL) audio power amplifier
and a single-ended (SE) stereo headphone amplifier. Oper-
ating on a single 5V supply, the mono BTL mode delivers 2W
(typ) to a 4
load (Note 1) at 0.3% THD+N. In SE stereo
mode, the amplifier will deliver 90mW to 32
loads. The
LM4913 features circuitry that suppresses output transients
("clicks and pops").
The LM4913 is designed for notebook and other handheld
portable applications. It delivers high quality output power
from a surface-mount package and requires few external
components. The LM4913 is pin and functionally compatible
with the TPA0213.
Other features include an active-low micro-power shutdown
mode and thermal shutdown protection.
The LM4913 is available a space efficient 10-lead exposed-
DAP TSSOP package.
Note 1:
When operating on a 5VDC supply, an LM4913MH that has been
properly mounted to a circuit board will deliver 2W into 4
. See the Applica-
tion Information sections for further information concerning PCB layout sug-
gestions to maximize the LM4913MH’s output power with a 4
load.
Key Specifications
j
BTL output power (R
L
= 4
)
V
DD
= at 3.0V, THD = 1%
V
DD
= at 5.0V, THD = 0.3%
j
SE output power (R
L
= 32
and THD = 0.1%)
V
DD
= at 3.0V
V
DD
= at 5.0V
j
Micro-power shutdown supply current
j
PSRR (
@
1kHz, 2.9V
≤
VDD
≤
5.1V, (Fig. 1))
BTL
SE
660mW (typ)
2W (typ)
33mW (typ)
90mW (typ)
1μA (typ)
52dB (typ)
62dB (typ)
Features
n
Advanced "click and pop" suppression circuitry
n
Stereo headphone amplifier mode
n
Low current micro-power shutdown mode
n
Thermal shutdown protection circuitry
n
2.5V to 5.5V operation
n
Unity-gain stable
n
Gain set with external resistors
n
Space-saving exposed-DAP TSSOP package
Applications
n
PDAs
n
Cellular phones
n
Handheld portable electronic devices
Connection Diagram
200617A0
Top View
Order Number LM4913MH
See NS package Number MXF10A
Boomer
is a registered trademark of National Semiconductor Corporation.
December 2002
L
2002 National Semiconductor Corporation
DS200617
www.national.com