WM8912: Ultra low power stereo DAC with headphone driver

Description

The WM8912 is a high performance ultra-low power stereo DAC optimised for portable audio applications.

The device features stereo ground-referenced headphone amplifiers using the Wolfson ‘Class-W’ amplifier techniques - incorporating an innovative dual-mode charge pump architecture - to optimise efficiency and power consumption during playback. The ground-referenced outputs eliminate headphone coupling capacitors. The outputs include common mode feedback paths to reject ground noise.

Control sequences for audio path setup can be pre-loaded and executed by an integrated control write sequencer to reduce software driver development and minimise pops and clicks via Wolfson’s SilentSwitch™ technology.

A dynamic range controller provides compression and level control to support a wide range of portable recording applications. Anti-clip and quick release features offer good performance in the presence of loud impulsive noises. ReTuneTM Mobile 5-band parametric equaliser with fully programmable coefficients is integrated for optimization of speaker characteristics.

Common audio sampling frequencies are supported from a wide range of external clocks, either directly or generated using the integrated FLL.

The WM8912 can operate directly from a single 1.8V switched supply. For optimal power consumption, the digital core can be operated from a 1.0V supply.

Features

  • 4mW quiescent power consumption for DAC to headphone playback
  • DAC SNR 96dB typical, THD -86dB typical
  • Class W ground-referenced headphone driver
    -  28mW per channel into 32Ω at <1% THD
    -  30mW per channel into 16Ω at <1% THD
  • Dynamic range controller
  • ReTune™ Mobile parametric equalizer
  • Integrated control write sequencer for pop minimised start-up and shutdown
  • Single register write for default start-up and shutdown sequences
  • On-chip FLL provides all necessary clocks
  • DAC supports standard sample rates from 8kHz to 48kHz
  • 32-pin QFN package (4x4mm, 0.4mm pitch)

Support