LM4990 Datasheet, PDF (1/19 Pages) National Semiconductor (TI) – 2 Watt Audio Power Amplifier with Selectable Shutdown Logic Level

January 2004
LM4990
2 Watt Audio Power Amplifier with Selectable Shutdown
Logic Level
General Description
The LM4990 is an audio power amplifier primarily designed
for demanding applications in mobile phones and other por-
table communication device applications. It is capable of
delivering 1.25 watts of continuous average power to an 8Ω
BTL load and 2 watts of continuous average power (LD and
MH only) to a 4Ω BTL load with less than 1% distortion
(THD+N+N) from a 5V_DC power supply.
Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components. The LM4990 does not require output
coupling capacitors or bootstrap capacitors, and therefore is
ideally suited for mobile phone and other low voltage appli-
cations where minimal power consumption is a primary re-
quirement.
The LM4990 features a low-power consumption shutdown
mode. To facilitate this, Shutdown may be enabled by either
logic high or low depending on mode selection. Driving the
shutdown mode pin either high or low enables the shutdown
pin to be driven in a likewise manner to enable shutdown.
The LM4990 contains advanced pop & click circuitry which
eliminates noise which would otherwise occur during turn-on
and turn-off transitions.
The LM4990 is unity-gain stable and can be configured by
external gain-setting resistors.
Key Specifications
j Improved PSRR at 217Hz & 1KHz
j Power Output at 5.0V, 1%
THD+N,
4Ω (LD and MH only)
j Power Output at 5.0V, 1% THD+N, 8Ω
j Power Output at 3.0V, 1% THD+N, 4Ω
j Power Output at 3.0V, 1% THD+N, 8Ω
j Shutdown Current
62dB
2W (typ)
1.25W (typ)
600mW (typ)
425mW (typ)
0.1µA (typ)
Features
n Available in space-saving packages: LLP, Exposed-DAP
TSSOP, MSOP, and ITL
n Ultra low current shutdown mode
n Improved pop & click circuitry eliminates noise during
turn-on and turn-off transitions
n 2.2 - 5.5V operation
n No output coupling capacitors, snubber networks or
bootstrap capacitors required
n Unity-gain stable
n External gain configuration capability
n User selectable shutdown High or Low logic Level
Applications
n Mobile Phones
n PDAs
n Portable electronic devices
Connection Diagrams
Mini Small Outline (MSOP) Package
MSOP Marking
200510B9
Top View
Order Number LM4990MM
See NS Package Number MUA08A
Boomer^® is a registered trademark of National Semiconductor Corporation.
© 2004 National Semiconductor Corporation DS200510
20051071
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Z - Plant Code
X - Date Code
TT - Die Traceability
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A5 - LM4990MM
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