LM4857 - Stereo 1.2W Audio Sub-system with 3D Enhancement

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	LM4857 - Stereo 1.2W Audio Sub-system with 3D Enhancement

Datasheet	Packaging	Samples & Pricing	Reliability	Application Notes	Knowledge Base

Features

•	Stereo speaker amplifier
•	Stereo headphone amplifier
•	Mono earpiece amplifier
•	Mono Line Output for external handsfree carkit
•	Independent Left, Right, and Mono volume controls
•	National 3D enhancement
•	I²C compatible interface
•	Ultra low shutdown current
•	Click and Pop Suppression circuit
•	16 distinct output modes
•	Thermal Shutdown Protection
•	Available in micro SMD and LLP packages

Key Specification

P_OUT, Stereo Loudspeakers, 4, 5V, 1% THD+N (LM4857SP)	1.6W (typ)
P_OUT, Stereo Loudspeakers, 8, 5V, 1% THD+N	1.2W (typ)
P_OUT, Stereo Headphones, 32, 5V, 1% THD+N	75mW (typ)
P_OUT, Mono Earpiece, 32, 5V, 1% THD+N	100mW (typ)
P_OUT, Stereo Loudspeakers, 8, 3.3V, 1% THD+N	495mW (typ)
P_OUT, Stereo Headphones, 32, 3.3V, 1% THD+N	33mW (typ)
P_OUT, Mono Earpiece, 32, 3.3V, 1% THD+N	43mW (typ)
Shutdown Current	0.06µA (typ)

General Description

The LM4857 is an integrated audio sub-system designed for stereo cell phone applications. More...

Applications

•	Cell Phones
•	PDAs
•	Portable Gaming Devices
•	Internet Appliances
•	Portable DVD/CD/AAC/MP3 players

Typical Application

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Parametric Table expand

Parametric Table collapse

Power@ 4Ohms, 10% THD Undefined Watt

Power@ 4Ohms, 1% THD Undefined Watt

Power@ 8Ohms, 10% THD 1.5 Watt

Power@ 8Ohms, 1% THD 1.2 Watt

THD 0.05 %

PSRR 70 dB

SNR Undefined dB

Channels 6 Channels

THD Conditions Speaker; Po=400mW, 8Ohm BTL

THD Conditions Speaker; Po=400mW, 8Ohm BTL

PSRR Conditions Speaker; Mode 2,3,7,8; Audio inputs terminated

PSRR Conditions Speaker; Mode 2,3,7,8; Audio inputs terminated

Power@ 4Ohms, 10% THD Undefined Watt

Power@ 4Ohms, 1% THD Undefined Watt

Power@ 8Ohms, 10% THD 1.5 Watt

Power@ 8Ohms, 1% THD 1.2 Watt

THD 0.05 %

PSRR 70 dB

SNR Undefined dB

Channels 6 Channels

THD Conditions Speaker; Po=400mW, 8Ohm BTL

PSRR Conditions Speaker; Mode 2,3,7,8; Audio inputs terminated

User Supply 5 Volt

Audio Mux Yes

Capless Headphone No

ClassD Driver No

Interface I2C

Stereo Inputs 1

National 3D Yes

Digital Volume Control Max 6 dB

Digital Volume Control Min -40.5 dB

Output Modes 16

Supply Range +2.7 - +5.5 V

Mono Inputs 1

Temperature Min -40 deg C

Temperature Max 85 deg C

Loudspeaker Type Class AB

Headphone Type Cap Coupled

Loudspeaker Outputs 2

View Using Catalog

Typical Performance

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Additional Resources

Application Notes (see below)

Connection Diagram

click for larger image

Datasheet

RoHS Compliance Information	Size in Kbytes	Date
LM4857 Boomer ® Audio Power Amplifier Series Stereo 1.2W Audio Sub-system with 3D Enhancement	1814 Kbytes	8-Jun-05	View Online	Download	Receive via Email

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Package Availability, Models, Samples & Pricing

Part Number

Package

Factory Lead Time

Models

Samples &
Electronic
Orders

Budgetary Pricing

Std
Pack
Size

Package
Marking
Format

Type

Pins

Spec.

MSL
Rating

Peak
Reflow

RoHS
Report

CAD
Symbols

Weeks

Qty

$US each

LM4857SP

LLP

NOPB

260

RoHS

Download

Full production

N/A

1K+

$2.15

reel
of
1000

NS
UZXYTT
L4857SP

12 weeks

1000

LM4857SPX

LLP

NOPB

260

RoHS

Download

Lifetime buy

N/A

1K+

$2.15

reel
of
4500

NS
UZXYTT
L4857SP

12 weeks

N/A

LM4857ITL

MICRO SMD

NOPB

260

RoHS

Download

Full production

N/A

1K+

$2.20

reel
of
250

XVG
I C2

8 weeks

500

LM4857ITLX

MICRO SMD

NOPB

260

RoHS

Download

Full production

N/A

1K+

$2.20

reel
of
3000

XVG
I C2

6 weeks

150000

Obsolete Parts

Obsolete Part	Alternate Part or Supplier	Source	Last Time Buy Date
LM4857GRBD	LM4857ITLBD	NATIONAL SEMICONDUCTOR CORP	11/16/2008
LM4857SPX	LM4857ITLX	NATIONAL SEMICONDUCTOR CORP	11/16/2008

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 delivering 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 package. In addition, the LM4857 routes and mixes the stereo and mono inputs into 16 distinct output modes. The LM4857 is controlled through an I²C compatible interface. Other features include an ultra-low current shutdown mode and thermal 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 28-lead LLP package.

Reliability Metrics

Part Number	Process	Early Failure Rate - Rejects	Sample Size (EFR)	PPM *	Rel. Rejects	Device Hours	Long Term Failure Rates (FITS)	MTTF
LM4857ITL	CS065	0	16225	0	0	1480000	3	419954041
LM4857ITLX	CS065	0	16225	0	0	1480000	3	419954041
LM4857SP	CS065	0	16225	0	0	1480000	3	419954041
LM4857SPX	CS065	0	16225	0	0	1480000	3	419954041

For more information on Reliability Metrics, please click here.

Application Notes

Title	Size in Kbytes	Date
AN-1076: Application Note 1076 Using the COP8ACC with Integration "A/D" Application Considerations	115 Kbytes	26-Jun-97	View Online	Download	Receive via Email

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[Information as of 17-May-2008]

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