EVAL-SSM2518Z: Stereo 2.5W x 2 @ 4Ω, Class D

The SSM2518 is a digital input, Class-D power amplifier that combines a digital-to-analog converter (DAC) and a sigma-delta Class-D modulator. This unique architecture enables extremely low real-world power consumption from digital audio sources with excellent audio performance. The SSM2518 is ideal for power sensitive applications, such as mobile phones and portable media players, where system noise can corrupt small analog signals such as those sent to an analog input audio amplifier.

Input is provided via a serial audio interface, programmable to accept all common audio formats including I2S and TDM. Control of the IC is provided via an I2C control interface. The SSM2518 can accept a variety of input MCLK frequencies and can use BCLK as the clock source in some configurations. Additional features include a soft digital volume control, de-emphasis, and a programmable digital dynamic range compressor.

Using the SSM2518, audio data can be transmitted to the amplifier over a standard digital audio serial interface, thereby significantly reducing the effect of noise sources such as GSM interference or other digital signals on the transmitted audio. The closed-loop digital input design retains the benefits of an all-digital amplifier, yet enables very good PSRR and audio performance. The three level, sigma-delta Class-D modulator is designed to provide the least amount of EMI interference, the lowest quiescent power dissipation, and the highest audio efficiency without sacrificing audio quality.