LM4681 Datasheet | National Semiconductor

Description The LM4681 is a fully integrated single supply, CLASS D audio power amplifier solution. The LM4681 utilizes a proprietary balanced pulse-width modulation technique that lowers output noise and THD and improves PSRR when pared to conventional pulse width modulators. The LM4681 also features a stereo headphone amplifier that delivers 80m W into a 32Ω headset with less than 0.5% THD. The LM4681’s I2C/SPI (selectable) volume control has a +30d B to - 48d B range when speakers are driven and a range of +13d B to - 65d B when headphones are connected. All amplifiers are protected by thermal shutdown. Additionally, the high efficiency power amplifiers have output current limit. With a 8Ω load, the IC’s efficiency for a 6W power level is 85%. The IC features click and pop reduction circuitry that minimizes audible popping during device turn-on and turnoff. The LM4681 is available in a 48-lead LLP package, ideal for portable and desktop puter applications. Key Specifications n n n n n n...