LM4888 Boomer ® Audio Power Amplifier Series Dual 2.1W Audio Amplifier Plus Stereo Headphone & 3D Enhancement
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 4
load (Note 1) or 2.4W to a 3 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 4
. 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 3
.
Key Specifications
j
P
O
at 1% THD+N, V
DD
= 5V
R
L
= 3
2.4W (typ)
R
L
= 4
2.1W (typ)
R
L
= 8
1.3W (typ)
j
Single-ended mode THD+N
at 75mW into 32
(5V, 1kHz)
0.01% (typ)
j
Shutdown current
0.04A (typ)
j
Supply voltage range
2.7V to 5.5V
j
PSRR at 217Hz
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
20111602
Top View
Order Number LM4888SQ
See NS Package Number SQA24A
201116C6
Top View
U = Fab Code
Z = Assembly Plant Code
XY = Date Code
TT = Die Traceability
Boomer
is a registered trademark of National Semiconductor Corporation.
June 2005
LM4888
Dual
2.1W
Audio
Amplifier
Plus
Stereo
Headphone
&
3
D
Enhancement
2005 National Semiconductor Corporation
DS201116
www.national.com
Typical Application
20111601
FIGURE 1. Typical Audio Amplifier Application Circuit
LM4888
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2
Absolute Maximum Ratings
(Note 3)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage
6.0V
Storage Temperature
-65C to +150C
Input Voltage
-0.3V to V
DD
+0.3V
Power Dissipation (Note 4)
Internally limited
ESD Susceptibility (Note 5)
2000V
ESD Susceptibility (Note 6)
200V
Junction Temperature
150C
Solder Information
Small Outline Package
Vapor Phase (60 sec.)
215C
Infrared (15 sec.)
220C
Thermal Resistance
JC
(typ) -- SQA24B
3C/W
JA
(typ) -- SQA24B
42C/W
Operating Ratings
Temperature Range
T
MIN
T
A
T
MAX
-40C
T
A
85C
Supply Voltage
2.7V
V
DD
5.5V
Electrical Characteristics (5V)
(Notes 3, 7, 13)
The following specifications apply for V
DD
= 5V unless otherwise noted. Limits apply for T
A
= 25C.
Symbol
Parameter
Conditions
LM4888
Units
(Limits)
Typical
Limit
(Note 8)
(Note 9)
V
DD
Supply Voltage
2.7
V (min)
5.5
V (max)
I
DD
Quiescent Power Supply Current
V
IN
= 0V, I
O
= 0A (Note 10) , BTL mode
6
10
mA (max)
V
IN
= 0V, I
O
= 0A (Note 10) , SE mode
3.0
6
mA (max)
I
SD
Shutdown Current
GND applied to the SHUTDOWN pin
0.04
2
A (max)
V
IH
Headphone Sense High Input
Voltage
3.7
4
V (min)
V
IL
Headphone Sense Low Input
Voltage
2.6
0.8
V (max)
V
IHSD
Shutdown, Headphone micro,
3D control
High Input voltage
1.2
1.4
V (min)
V
ILSD
Shutdown, Headphone micro,
3D control
Low Input voltage
1
0.4
V (max)
T
WU
Turn On Time
1F Bypass Cap (C6)
140
ms
Electrical Characteristics for Bridged-Mode Operation (5V)
(Notes 3, 7, 13)
The following specifications apply for V
DD
= 5V unless otherwise specified. Limits apply for T
A
= 25C.
Symbol
Parameter
Conditions
LM4888
Units
(Limits)
Typical
Limit
(Note 8)
(Note 9)
V
OS
Output Offset Voltage
V
IN
= 0V
5
25
mV (max)
P
O
Output Power (Note 11)
THD+N = 1%, f = 1kHz (Note 12)
LM4888SQ, R
L
= 3
2.4
W
LM4888SQ, R
L
= 4
2.1
W
LM4888SQ, R
L
= 8
1.3
1.0
W (min)
THD+N = 10%, f = 1kHz (Note 12)
LM4888SQ, R
L
= 3
3.0
W
LM4888SQ, R
L
= 4
2.5
W
LM4888SQ, R
L
= 8
1.7
W
LM4888
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3
Electrical Characteristics for Bridged-Mode Operation (5V)
(Notes 3, 7,
13) (Continued)
The following specifications apply for V
DD
= 5V unless otherwise specified. Limits apply for T
A
= 25C.
Symbol
Parameter
Conditions
LM4888
Units
(Limits)
Typical
Limit
(Note 8)
(Note 9)
THD+N
Total Harmonic Distortion+Noise
1kHz, A
VD
= 2
LM4888SQ, R
L
= 4
, P
O
= 1W
0.10
%
LM4888SQ, R
L
= 8
, P
O
= .4W
0.06
%
PSRR
Power Supply Rejection Ratio
Input Unterminated, 217Hz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 8
85
dB
Input Unterminated, 1kHz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 8
80
dB
Input grounded, 217Hz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 8
65
dB
Input grounded, 1kHz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 8
70
dB
X
TALK
Channel Separation
f = 1kHz, C
6
= 1.0F, 3D Control = Low
82
dB
V
NO
Output Noise Voltage
1kHz, A-weighted
21
V
Electrical Characteristics for Single-Ended Operation (5V)
(Notes 3, 7, 13)
The following specifications apply for V
DD
= 5V unless otherwise specified. Limits apply for T
A
= 25C.
Symbol
Parameter
Conditions
LM4888
Units
(Limits)
Typical
Limit
(Note 8)
(Note 9)
P
O
Output Power
THD+N = 0.5%, f = 1 kHz, R
L
= 32
90
75
mW (min)
THD+N
Total Harmonic Distortion+Noise
P
O
= 20mW, 1kHz, R
L
= 32
0.015
%
PSRR
Power Supply Rejection Ratio
Input Unterminated, 217Hz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 32
70
dB
Input Unterminated, 1kHz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 32
72
dB
Input grounded, 217Hz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 32
65
dB
Input grounded, 1kHz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 32
70
dB
X
TALK
Channel Separation
f = 1kHz, C
6
= 1.0F, 3D Control = Low
80
dB
V
NO
Output Noise Voltage
1kHz, A-weighted
11
V
LM4888
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4
Electrical Characteristics (3V)
(Notes 3, 7, 13)
The following specifications apply for V
DD
= 3V unless otherwise noted. Limits apply for T
A
= 25C.
Symbol
Parameter
Conditions
LM4888
Units
(Limits)
Typical
Limit
(Note 8)
(Note 9)
I
DD
Quiescent Power Supply Current
V
IN
= 0V, I
O
= 0A (Note 10) , BTL mode
4.5
mA
V
IN
= 0V, I
O
= 0A (Note 10) , SE mode
2.5
mA
I
SD
Shutdown Current
GND applied to the SHUTDOWN pin
0.01
A
V
IH
Headphone High Input Voltage
2.2
V
V
IL
Headphone Low Input Voltage
1.5
V
V
IHSD
Shutdown, Headphone micro,
3D Control
High Input voltage
1
1.4
V (min)
V
ILSD
Shutdown, Headphone micro,
3D Control
Low Input voltage
0.8
.4
V (max)
T
WU
Turn On Time
1F Bypass Cap (C6)
140
ms
Electrical Characteristics for Bridged-Mode Operation (3V)
(Notes 3, 7, 13)
The following specifications apply for V
DD
= 3V unless otherwise specified. Limits apply for T
A
= 25C.
Symbol
Parameter
Conditions
LM4888
Units
(Limits)
Typical
Limit
(Note 8)
(Note 9)
V
OS
Output Offset Voltage
V
IN
= 0V
5
mV
P
O
Output Power (Note 11)
THD+N = 1%, f = 1kHz (Note 12)
LM4888SQ, R
L
= 3
.82
W
LM4888SQ, R
L
= 4
.70
W
LM4888SQ, R
L
= 8
.43
W
THD+N = 10%, f = 1kHz (Note 12)
LM4888SQ, R
L
= 3
1.0
W
LM4888SQ, R
L
= 4
.85
W
LM4888SQ, R
L
= 8
.53
W
THD+N
Total Harmonic Distortion+Noise
1kHz
LM4888SQ, R
L
= 4
, P
O
= 280mW
0.1
%
LM4888SQ, R
L
= 8
, P
O
= 200mW
0.05
%
PSRR
Power Supply Rejection Ratio
Input Unterminated, 217Hz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 8
90
dB
Input Unterminated, 1kHz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 8
80
dB
Input grounded, 217Hz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 8
65
dB
Input grounded, 1kHz
V
ripple
= 200mV
p-p
C
6
= 1F, R
L
= 8
73
dB
X
TALK
Channel Separation
f = 1kHz, C
6
= 1.0F, 3D Control = Low
85
dB
V
NO
Output Noise Voltage
1kHz, A-weighted
21
V
LM4888
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5
Document Outline
- LM4888 Boomer (R) Audio Power Amplifier Series
- General Description
- Key Specifications
- Features
- Applications
- Connection Diagrams
- Typical Application
- Absolute Maximum Ratings
- Operating Ratings
- Electrical Characteristics (5V) (Notes , , )
- Electrical Characteristics for Bridged-Mode Operation (5V) (Notes , , )
- Electrical Characteristics for Single-Ended Operation (5V) (Notes , , )
- Electrical Characteristics (3V) (Notes , , )
- Electrical Characteristics for Bridged-Mode Operation (3V) (Notes , , )
- Electrical Characteristics for Single-Ended Operation (3V) (Notes , , )
- Typical Performance Characteristics
- Application Information
- Demonstration Board Layout
- Bill of Materials
- Revision History
- Physical Dimensions
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