The LM48311 is a single supply, high efficiency, mono, 2.6W, filterless switching audio amplifier. The LM48311 features National's Enhanced Emissions Suppression (E2S) system, that features a unique patent-pending ultra low EMI, spread spectrum, PWM architecture, that significantly reduces RF emissions while preserving audio quality and efficiency. The E2S system improves battery life, reduces external component count, board area consumption, system cost, and simplifying design. The LM48311 is designed to meet the demands of portable multimedia devices. Operating from a single 5V supply, the device is capable of delivering 2.6W of continuous output power to a 4 load with less than 10% THD+N. Flexible power supply requirements allow operation from 2.4V to 5.5V. The LM48311 features both a spread spectrum modulation scheme, and an advanced, patented edge rate control (ERC) architecture that significantly reduces emissions, while maintaining high quality audio reproduction (THD+N = 0.03%) and high efficiency ( = 88%).