Wolfson WM8912超低功耗立体声DAC评估方案

Wolfson公司的WM8912 是高性能超低功耗立体声DAC,非常适合手提音频应用. WM8912具有采用Wolfson”W类”放大器技术的参考地立体声耳机放大器,每路向16欧姆提供30mW时的THD小于1%,DAC的SNR典型值为96dB,THD为-86dB, 主要用于手提多媒体播放器,多媒体手机和手持游戏机.本文介绍WM8912主要特性,方框图,以及评估板WM8912-6201-FL32-M 电路和所用材料清单(BOM).
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.
WM8912主要特性:
• 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...