SSM2335 Filterless, High Efficiency, Mono 3 W Class-D Audio Amplifier

The SSM2335 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 Ω load from a 5.0 V supply.

The SSM2335 features a high efficiency, low noise modulation scheme that requires no external LC output filters. The modu-lation continues to provide high efficiency even at low output power. It operates with 93% efficiency at 1.4 W into 8 Ω or 85% efficiency at 3 W into 3 Ω from a 5.0 V supply and has an SNR of >96 dB. Spread-spectrum pulse density modulation is used to provide lower EMI-radiated emissions compared with other Class-D architectures.

The SSM2335 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 suppression circuitry minimizes voltage glitches at the output during turn-on and turn-off, reducing audible noise on activation and deactivation.

The fully differential input of the SSM2335 provides excellent rejection of common-mode noise on the input. Input coupling capacitors can be omitted if the input dc common-mode voltage is approximately VDD/2.

The default gain of the SSM2335 is 18 dB, but users can reduce the gain by using a pair of external resistors .

The SSM2335 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).

Applications
  • Mobile phones
  • MP3 players
  • Portable gaming
  • Portable electronics
  • Educational toys
Features and Benefits
  • Filterless Class-D amplifier with Σ-Δ modulation
  • No sync necessary when using multiple Class-D amplifiers from Analog Devices, Inc.
  • 3 W into 3 Ω load and 1.4 W into 8 Ω load at 5.0 V supply with <1% total harmonic distortion (THD + N)
  • 93% efficiency at 5.0 V, 1.4 W into 8 Ω speaker
  • >96 dB signal-to-noise ratio (SNR)
  • Single-supply operation from 2.5 V to 5.5 V
  • 20 nA ultralow shutdown current
  • Short-circuit and thermal protection
  • Available in 9-ball, 1.5 mm × 1.5 mm WLCSP
  • Pop-and-click suppression
  • Built-in resistors reduce board component count
  • Default fixed 18 dB or user-adjustable gain setting
  • Audio & Video Products
    Data Sheets
    Documentnote
    SSM2335: Filterless, High Efficiency, Mono 3 W Class-D Audio Amplifier Data Sheet (Rev. 0)PDF 577 kB
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    SSM2335CBZ-REEL Contact ADI9 ball WLCSP (1.46x1.46)REEL 10000-40 to 85C00.57Y
    SSM2335CBZ-REEL7 Contact ADI9 ball WLCSP (1.46x1.46)REEL 3000-40 to 85C00.57Y
    Evaluation Boards
    Part NumberDescriptionPriceRoHS
    EVAL-SSM2335ZEvaluation Board50.5Y
    SSM2335: Filterless, High Efficiency, Mono 3 W Class-D Audio Amplifier Data Sheet (Rev. 0) ssm2335