LM4857
Stereo 1.2W Audio Sub-system with 3D Enhancement
General Description
The LM4857 is an integrated audio sub-system designed for
stereo cell phone applications. Operating on a 3.3V supply, it
combines a stereo speaker amplifier delivering 495mW per
channel into an 8
load, a stereo headphone amplifier de-
livering 33mW per channel into a 32
load, a mono earpiece
amplifier delivering 43mW into a 32
load, and a line output
for an external powered handsfree speaker. It integrates the
audio amplifiers, volume control, mixer, power management
control, and National 3D enhancement all into a single pack-
age. In addition, the LM4857 routes and mixes the stereo
and mono inputs into 16 distinct output modes. The LM4857
is controlled through an I
2
C compatible interface. Other fea-
tures include an ultra-low current shutdown mode and ther-
mal shutdown protection.
Boomer audio power amplifiers are designed specifically to
provide high quality output power with a minimal amount of
external components.
The LM4857 is available in a 30-bump ITL package and a
28lead LLP package.
Key Specifications
j
P
OUT
, Stereo Loudspeakers, 4
, 5V,
1% THD+N (LM4857SP)
1.6W (typ)
j
P
OUT
, Stereo Loudspeakers, 8
, 5V,
1% THD+N
1.2W (typ)
j
P
OUT
, Stereo Headphones, 32
, 5V,
1% THD+N
75mW (typ)
j
P
OUT
, Mono Earpiece, 32
, 5V,
1% THD+N
100mW (typ)
j
P
OUT
, Stereo Loudspeakers, 8
, 3.3V,
1% THD+N
495mW (typ)
j
P
OUT
, Stereo Headphones, 32
, 3.3V,
1% THD+N
33mW (typ)
j
P
OUT
, Mono Earpiece, 32
, 3.3V,
1% THD+N
43mW (typ)
j
Shutdown Current
0.06A (typ)
Features
n
Stereo speaker amplifier
n
Stereo headphone amplifier
n
Mono earpiece amplifier
n
Mono Line Output for external handsfree carkit
n
Independent Left, Right, and Mono volume controls
n
National 3D enhancement
n
I
2
C compatible interface
n
Ultra low shutdown current
n
Click and Pop Suppression circuit
n
16 distinct output modes
n
Thermal Shutdown Protection
n
Available in micro SMD and LLP packages
Applications
n
Cell Phones
n
PDAs
n
Portable Gaming Devices
n
Internet Appliances
n
Portable DVD/CD/AAC/MP3 players
Boomer
is a registered trademark of National Semiconductor Corporation.
June 2004
LM4857
Stereo
1.2W
Audio
Sub-system
with
3D
Enhancement
2004 National Semiconductor Corporation
DS200797
www.national.com
Connection Diagrams
30 Bump ITL Package
micro SMD Marking
200797A9
Top View
(Bump-side down)
Order Number LM4857ITL
See NS Package Number TLA30CZA
200797I3
Top View
X -- Date Code
T -- Die Traceability
G -- Boomer Family
C2 -- LM4857ITL
Pin Connection (ITL)
Pin
Name
Pin Description
A1
RLS+
Right Loudspeaker Positive Output
A2
V
DD
Power Supply
A3
SDA
Data
A4
RHP3D
Right Headphone 3D
A5
RHP
Right Headphone Output
B1
GND
Ground
B2
I
2
CV
DD
I
2
C Interface Power Supply
B3
ADR
I
2
C Address Select
B4
LHP3D
Left Headphone 3D
B5
V
DD
Power Supply
C1
RLS-
Right Loudspeaker Negative Output
C2
NC
No Connect
C3
SCL
Clock
C4
LINEOUT
Mono Line Output
C5
GND
Ground
D1
LLS-
Left Loudspeaker Negative Output
D2
V
DD
Power Supply
D3
M
IN
Mono Input
D4
NC
No Connect
D5
EP+
Mono Earpiece Positive Output
E1
GND
Ground
E2
BYPASS
Half-supply bypass
E3
LLS3D
Left Loudspeaker 3D
E4
R
IN
Right Stereo Input
E5
EP-
Mono Earpiece Negative Output
F1
LLS+
Left Loudspeaker Positive Output
F2
V
DD
Power Supply
F3
RLS3D
Right Loudspeaker 3D
F4
L
IN
Left Stereo Input
F5
LHP
Left Headphone Output
LM4857
www.national.com
3
Connection Diagrams
49 Bump GR Package
micro Array Marking
200797I4
Top View
(Bump-side down)
Order Number LM4857GR
See NS Package Number GRA49A
(available soon)
200797I3
Top View
X -- Date Code
T -- Die Traceability
G -- Boomer Family
B6 -- LM4857GR
Pin Connection (GR)
Pin
Name
Pin Description
A1
NC
No Connect
A2
LHP3D
Left Headphone 3D
A3
SCL
Clock
A4
ADR
I
2
C Address Select
A5
I
2
CV
DD
I
2
C Interface Power Supply
A6
RLS-
Right Loudspeaker Negative Output
A7
RLS-
Right Loudspeaker Negative Output
B1
RHP
Right Headphone Output
B2
NC
No Connect
B3
RHP3D
Right Headphone 3D
B4
SDA
Data
B5
VDD
Power Supply
B6
GND
Ground
B7
GND
Ground
C1
LINEOUT
Mono Line Output
C2
VDD
Power Supply
C3, C4, C5
NC
No Connect
C6
RLS+
Right Loudspeaker Positive Output
C7
RLS+
Right Loudspeaker Positive Output
D1
GND
Ground
D2, D3, D4, D5
NC
No Connect
D6
LLS+
Left Loudspeaker Positive Output
D7
VDD
Power Supply
E1
EP-
Mono Earpiece Negative Output
E2
EP+
Mono Earpiece Positive Output
LM4857
www.national.com
4
Pin Connection (GR)
(Continued)
E3, E4, E5
NC
No Connect
E6
GND
Ground
E7
LLS+
Left Loudspeaker Positive Output
F1
LHP
Left Headphone Output
F2
NC
No Connect
F3
L
IN
Left Stereo Input
F4
LLS3D
Left Loudspeaker 3D
F5
VDD
Power Supply
F6
LLS-
Left Loudspeaker Negative Output
F7
GND
Ground
G1
NC
No Connect
G2
R
IN
Right Stereo Input
G3
M
IN
Mono Input
G4
RLS3D
Right Loudspeaker 3D
G5
BYPASS
Half-supply bypass
G6
NC
No Connect
G7
LLS-
Left Loudspeaker Negative Output
Connection Diagram
28 Lead SP Package
20079799
Top View
Order Number LM4857SP
See NS Package Number SPA28A
LM4857
www.national.com
5
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