LM4857 Datasheet | National Semiconductor

Description The LM4857 is an integrated audio sub-system designed for stereo cell phone applications. Operating on a 3.3V supply, it bines a stereo speaker amplifier delivering 495m W per channel into an 8Ω load, a stereo headphone amplifier delivering 33m W per channel into a 32Ω load, a mono earpiece amplifier delivering 43m W into a 32Ω 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 patible 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 ponents. The LM4857 is available in a 30-bump ITL package and a 28- lead LLP package. Key Specifications j POUT, Stereo Loudspeakers, 4Ω, 5V, 1% THD+N (LM4857SP) j POUT, Stereo Loudspeakers, 8Ω, 5V, 1.6W (typ) 1.2W (typ) 75m W (typ) 100m W (typ) 495m W (typ) 33m W (typ) 43m W (typ) 0.06µA (typ) 1% THD+N j POUT, Stereo Headphones, 32Ω, 5V, 1% THD+N j POUT, Mono Earpiece, 32Ω, 5V, 1% THD+N j POUT, Stereo Loudspeakers, 8Ω, 3.3V, 1% THD+N j POUT, Stereo Headphones, 32Ω, 3.3V, 1% THD+N j POUT, Mono Earpiece, 32Ω, 3.3V, 1% THD+N j Shutdown Current Features n n n n n n n n n n n n 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 patible interface Ultra low shutdown current Click and Pop Suppression circuit 16 distinct output modes Thermal Shutdown Protection Available in micro SMD and LLP packages Applications n n n n n Cell Phones PDAs Portable Gaming Devices Internet Appliances Portable DVD/CD/AAC/MP3...