The document describes a filterless high efficiency mono 2.8 W class-D audio amplifier, SSM2305 Rev. A, which features Σ-Δ modulation, no sync necessary when using multiple class-D amplifiers, 2.8 W output into 4 Ω load, 1.6 W output into 8 Ω load, 89% efficiency, >98 dB signal-to-noise ratio, single-supply operation from 2.5 V to 5.5 V, 20 nA ultralow shutdown current, short-circuit and thermal protection, available in 8-lead, 3 mm × 3 mm LFCSP and MSOP packages, pop-and-click suppression, built-in resistors to reduce board component count, and fixed and user-adjustable gain configurations.
The SSM2305 is a fully integrated, filter‑less Class‑D audio amplifier designed for mobile and portable electronics. It operates from a single 2.5 V to 5.5 V supply and can deliver up to 2.8 W into a 4 Ω load with 89 % efficiency. The device includes pop‑and‑click suppression, short‑circuit and thermal protection, and a built‑in shutdown mode with ultra‑low current draw.
Typical applications include mobile phones, MP3 players, portable gaming devices, and educational toys. The amplifier features a high‑efficiency modulation scheme that eliminates the need for external LC output filters, providing low EMI and excellent power‑supply noise rejection.
| Efficiency (1.3 W into 8 Ω) | 89 % |
|---|---|
| Signal‑to‑Noise Ratio | >98 dB |
| Supply Voltage Range | 2.5 V to 5.5 V |
| Closed‑Loop Gain | 18 dB |
The device operates from a single supply of 2.5 V to 5.5 V.
The amplifier achieves 89 % efficiency at that output level.
The SNR is greater than 98 dB.