EVAL-SSM3302Z: 8W x2 @ 8Ω, 7 ~ 18V in, Class D

The SSM3302 is a fully integrated, high efficiency, stereo Class-D audio amplifier. The application circuit requires a minimum of external components and operates from a single 7 V to 18 V supply. It is capable of delivering 2 × 8 W of continuous output power into an 8 Ω load (or 2 × 10 W into 4 Ω) with <1% total harmonic distortion plus noise (THD + N) from a 12 V supply. In addition, while mono mode is active, a load as small as 2 Ω up to 20 W continuous output power can be driven by stacking the stereo output terminals.

Spread spectrum pulse density modulation is used to provide lower EMI-radiated emissions compared with other Class-D architectures. The SSM3302 includes an optional modulation select pin (ultralow EMI emission mode) that significantly reduces the radiated emissions at the Class-D outputs, particularly above 100 MHz. The SSM3302 can pass FCC Class-B emissions testing with an unshielded 20 inch cable using common-mode choke-based filtering.

The fully differential input of the SSM3302 provides excellent rejection of common-mode noise on the input. The device also includes a highly flexible gain select pin that only requires one series resistor to choose any of the five gain options between 9 dB and 24 dB, with no change to the input impedance. The benefit of this is to improve gain matching between multiple SSM3302 devices within a single application compared to using external resistors to set gain.

The user guide describes how to configure and use the SSM3302 evaluation board. The user guide should be read in conjunction with the SSM3302 data sheet, which provides specifications, internal block diagrams, and application guidance for the amplifier IC.

The SSM3302 evaluation board carries a complete circuit for driving a pair of loudspeakers.