LM4888_06 Datasheet, PDF (1/23 Pages) National Semiconductor (TI) – Dual 2.1W Audio Amplifier Plus Stereo Headphone & 3D Enhancement

March 2006
LM4888
Dual 2.1W Audio Amplifier Plus Stereo Headphone & 3D
Enhancement
General Description
The LM4888 is a dual bridge-connected audio power ampli-
fier which, when connected to a 5V supply, will deliver 2.1W
to a 4Ω load (Note 1) or 2.4W to a 3Ω load (Note 2) with less
than 1.0% THD+N.
A user selectable “National 3D Enhancement” mode pro-
vides enhanced stereo imaging.
The LM4888SQ also has two separate HP (headphone)
enable inputs, each having different logic level thresholds.
Either HP enable input activates the single ended head-
phone mode and disables the BTL output mode. The HP
Sense input is for use with a normal stereo headphone jack.
The remaining input, HP Logic, accepts standard logic level
thresholds.
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 LM4888SQ combines dual
bridge speaker amplifiers and stereo headphone amplifiers
on one chip.
The LM4888SQ features a low-power consumption shut-
down mode and thermal shutdown protection. It also utilizes
circuitry to reduce “clicks and pops” during device turn-on.
Note 1: An LM4888SQ that has been properly mounted to a circuit board
will deliver 2.1W into 4Ω. See the Application Information sections for further
information concerning the LM4888SQ.
Note 2: An LM4888SQ that has been properly mounted to a circuit board
and forced-air cooled will deliver 2.4W into 3Ω.
Key Specifications
j P_O at 1% THD+N, V_DD = 5V
R_L = 3Ω
R_L = 4Ω
R_L = 8Ω
j Single-ended mode THD+N
at 75mW into 32Ω (5V, 1kHz)
j Shutdown current
j Supply voltage range
j PSRR at 217Hz
2.4W (typ)
2.1W (typ)
1.3W (typ)
0.01% (typ)
0.04µA (typ)
2.7V to 5.5V
85dB (typ)
Features
n National 3D Enhancement
n Selectable headphone enable modes
n Stereo headphone amplifier mode
n Improved “click and pop” suppression circuitry
n Thermal shutdown protection circuitry
n PCB area-saving SQ package
n Micro power shutdown mode
Applications
n Cell phones
n Multimedia monitors
n Portable and desktop computers
n Portable audio systems
Connection Diagrams
LM4888SQ
LM4888SQ Top Mark
20111628
Top View
Order Number LM4888SQ
See NS Package Number SQA24A
Boomer^® is a registered trademark of National Semiconductor Corporation.
© 2006 National Semiconductor Corporation DS201116
201116C6
Top View
U = Fab Code
Z = Assembly Plant Code
XY = Date Code
TT = Die Traceability
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