ADI SSM2380CBZ-REEL7

The SSM2380 is a fully integrated, high-efficiency Class D stereo audio amplifier designed for maximum performance in mobile phone applications. The application circuit requires minimal external components and operates from a single 2.5 V to 5.5 V supply. With a 5.0 V supply, it delivers 2 W continuous output power into a 4 Ω load with THD+N less than 1%.

The SSM2380 features a highly flexible I²C interface with numerous useful settings. Using the I²C control interface, the gain of the SSM2380 can be selected from 1 dB to 24 dB, offering 47 options including mute, with no external components required. Additional features accessible via the I²C interface include: independent left/right channel shutdown, variable ultra-low EMI radiation control mode, automatic level control (ALC) for protecting high-quality speakers, and stereo-to-mono mixing operation.

The SSM2380 employs a high-efficiency, low-noise modulation scheme that eliminates the need for external LC output filters. This modulation scheme maintains high efficiency even at low output power levels. With a 5.0 V supply, efficiency is 93% at 1.4 W into an 8 Ω load and 85% at 2 W into a 4 Ω load, with SNR greater than 100 dB.

Compared to other Class D architectures, spread-spectrum pulse density modulation provides lower EMI. An additional benefit of spread-spectrum Σ-Δ modulation is that no SYNC signal is required when using multiple Class D amplifiers. For applications requiring long speaker cables (>10 cm), the SSM2380 includes a user-selectable ultra-low EMI radiation mode, eliminating the need for EMI filters at the Class D outputs.

The SSM2380 features a micropower shutdown mode with a typical shutdown current of 20 nA. Applying a logic low to the SD pin enables shutdown mode, and any channel can be soft-shutdown via the I²C interface.

The device also incorporates a pop-and-click suppression circuit that minimizes voltage glitches at the output during power-on and power-off, thereby reducing audio noise during startup and shutdown.

The SSM2380 provides fully differential inputs for excellent common-mode noise rejection at the input. If the DC input common-mode voltage is approximately VDD/2, the input coupling capacitors can be omitted.

The SSM2380 is rated for the −40°C to +85°C commercial temperature range. It features integrated thermal shutdown and output short-circuit protection, and is available in a 16-ball, 2 mm × 2 mm WLCSP.

• MODE pin disables I²C interface for traditional stereo amplifier operation
• Stereo-to-mono mixer option configurable via I²C
• Efficiency: 93% (5.0 V, driving 8 Ω speaker at 1.4 W)
• SNR: > 100 dB
• 2.5 V to 5.5 V single-supply operation
• Ultra-low shutdown current: 20 nA
• Short-circuit and thermal protection
• Pop and click suppression
• 16-pin 2.0 mm × 2.0 mm WLCSP package

• Mobile phones
• MP3 players
• Portable electronic devices