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LM4857  Product Folder

Stereo 1.2W Audio Sub-system with 3D Enhancement
Generic P/N 4857
General
Description		 Features Datasheet Package
& Models		 Samples
& Pricing

Datasheet

TitleSize in KbytesDate
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LM4857 Boomer ® Audio Power Amplifier Series Stereo 1.2W Audio Sub-system with 3D Enhancement 1249 Kbytes 5-Dec-03 View Online Download Receive via Email

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Package Availability, Models, Samples & Pricing

Part NumberPackageStatusModelsSamples &
Electronic
Orders		Budgetary PricingStd
Pack
Size		Package
Marking
TypePinsMSL/Lead-Free AvailabilityLead
Time		QtySPICEIBISQty$US each
LM4857ITLmicroSMD30StatusFull productionN/AN/ASamples1K+$2.70reel
of
250		XVG
I C2
10 weeks0
LM4857ITLXmicroSMD30StatusFull productionN/AN/A 1K+$2.70reel
of
3000		XVG
I C2
10-12 weeks25000

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.

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

POUT, Stereo Loudspeakers, 8, 5V, 1% THD+N1.2W (typ)
POUT, Stereo Headphones, 32, 5V, 1% THD+N75mW (typ)
POUT, Mono Earpiece, 32, 5V, 1% THD+N100mW (typ)
POUT, Stereo Loudspeakers, 8, 3.3V, 1% THD+N495mW (typ)
POUT, Stereo Headphones, 32, 3.3V, 1% THD+N33mW (typ)
POUT, Mono Earpiece, 32, 3.3V, 1% THD+N43mW (typ)
Shutdown Current0.06µA (typ)

Applications

  • Cell Phones
  • PDAs
  • Portable Gaming Devices
  • Internet Appliances
  • Portable DVD/CD/AAC/MP3 players
[Information as of 15-Jan-2004]

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