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 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. Key Specification POUT, Stereo Loudspeakers, 4, 5V, 1% THD+N (LM4857SP) 1.6W (typ) POUT, Stereo Loudspeakers, 8, 5V, 1% THD+N 1.2W (typ) POUT, Stereo Headphones, 32, 5V, 1% THD+N 75mW (typ) POUT, Mono Earpiece, 32, 5V, 1% THD+N 100mW (typ) POUT, Stereo Loudspeakers, 8, 3.3V, 1% THD+N 495mW (typ) POUT, Stereo Headphones, 32, 3.3V, 1% THD+N 33mW (typ) POUT, Mono Earpiece, 32, 3.3V, 1% THD+N 43mW (typ) Shutdown Current 0.06µA (typ) Applications • Cell Phones • PDAs • Portable Gaming Devices • Internet Appliances • Portable DVD/CD/AAC/MP3 players

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Datasheet

Title		Size	Date	Other Language
	LM4857 Boomer ® Audio Power Amplifier Series Stereo 1.2W Audio Sub-system with 3D Enhancement	1814 Kbytes	8-Jun-05

Featured Application Notes

Title		Size	Date	Other Language
	AN-1611: Application Note 1611 LM48555 Evaluation Board	734 Kbytes	4-Apr-07

More Application Notes

Title		Size	Date	Other Language
	AN-1611: Application Note 1611 LM48555 Evaluation Board	734 Kbytes	4-Apr-07

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Standard Pack Size
LM4857SP/NOPB RoHS		Full production Lead Time: 6 weeks	Distributor Region Qty DIGIKEY Worldwide 1900	$2.15 each at 1K+ pcs	reel of 1000
LM4857ITL/NOPB RoHS	MICRO SMD	Full production Lead Time: 6 weeks	Distributor Region Qty DIGIKEY Worldwide 496 RS COMPONENTS Worldwide 248	$2.00 each at 1K+ pcs	reel of 250

Obsolete Versions

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

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM4857ITL	CS065	2	38968	52	0	4402000	1	1249079519
LM4857SP	CS065	2	38968	52	0	4402000	1	1249079519

Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

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Obsolete Versions

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