Wolfson WM8994智能手机多路音频CODEC方案

Wolfson公司的WM8994是高度集成智能手机用超低功耗高保真音频CODEC,具有高保真24位4路DAC和2路ADC,立体声DAC播放的SNR为100dB(A加权),1W立体声/2W单声道D类/AB类扬声器驱动器,无电容W类耳机驱动器,智能的MIC接口和高性能模拟MIC接口,主要应用在智能手机和音乐手机,手提导航仪和移动互联网设备(MID).本文介绍了WM8994主要特性,方框图, 采用数字MIC和数字音频接口的智能手机方框图以及WM8994评估板,功能方框图,详细电路图和所用材料清单(BOM).
The WM8994 is a highly integrated ultra-low power hi-fi CODEC designed for smartphones and other portable devices rich in multimedia features.
An integrated stereo class D/AB speaker driver and class W headphone driver minimize power consumption during audio playback.
The device requires only Vbatt and a 1.8V supply, generating all other internal supply rails from integrated LDOs.
Stereo full duplex asynchronous sample rate conversion and multi-channel digital mixing combined with powerful analogue mixing allow the device to support a huge range of different architectures and use cases.
A fully programmable parametric EQ provides speaker compensation and a dynamic range controller can be used in the ADC or DAC paths for maintaining a constant signal level, maximizing loudness and protecting speakers against overloading and clipping.
A smart digital microphone interface provides power regulation, a low jitter clock output and decimation filters for up to four digital microphones. A MIC activity detect with interrupt is available.
Active ground loop noise rejection and DC offset correction help prevent pop noise and suppress ground noise on the headphone outputs.
WM8994主要特性:
• Hi-Fi 24-bit 4-channel DAC and 2-channel ADC
• 100dB SNR during stereo DAC playback (‘A’ weighted)
• Smart MIC interface
- Power, clocking and data input for up to four digital MICs
- High performance analogue MIC interface
- MIC activity monitor & interrupt allows processor to sleep
• 1W stereo / 2W mo...