The SSM2319 is a fully integrated, high efficiency Class-D audio amplifier. It is designed to maximize performance for mobile phone applications. The application circuit requires a minimum of external components and operates from a single 2.5 V to 5.5 V supply. It is capable of delivering 3 W of continuous output power with <1% THD + N driving a 3 Ohms load from a 5.0 V supply. The SSM2319 features a high efficiency, low noise modulation scheme that does not require any external LC output filters. The modulation continues to provide high efficiency even at low output power. It operates with 90% efficiency at 1.4 W into 8 ? or 85% efficiency at 3 W into 3 Ohms from a 5.0 V supply and has an SNR of 98 dB. Spread-spectrum pulse density modulation is used to provide lower EMI-radiated emissions compared with other Class-D architectures. SYNC can be activated in the event that end users are concerned about clock intermodulation (beating effect) of several amplifiers in close proximity. The SSM2319 has a micropower shutdown mode with a typical shutdown current of 20 nA. Shutdown is enabled by applying a logic low to the SD pin. The device also includes pop-and-click suppression circuitry. This minimizes voltage glitches at the output during turn-on and turn-off, reducing audible noise on activation and deactivation. The default gain of the SSM2319 is 12 dB, but users can reduce the gain by using a pair of external resistors (see the Gain section). The SSM2319 is specified over the industrial temperature range of -40°C to +85°C. It has built-in thermal shutdown and output short-circuit protection. It is available in a 9-ball, 1.5 mm × 1.5 mm wafer level chip scale package (WLCSP).