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

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Part Number(s) (NSID)	Top View	Type	Pins	MSL Rating	Peak Reflow	RoHS Status	CAD Symbols	Models	Package Marking Format
LM4857ITL/NOPB		MICRO SMD	30	1	260	Detail	Download	N/A	XVG I C2
LM4857SP/NOPB LM4857SP		LLP	28	1 1	260 260	Detail	Download	N/A	NS UZXYTT L4857SP

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

Diagrams

Typical Application click for larger image	Connection Diagram click for larger image
Typical Performance click for larger image