WM8994: Multi-Channel CODEC with 3 digital audio interfaces


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.


  • 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 mono class D/AB speaker driver
  • Capless class W headphone drivers
    - Integrated charge pump
    - 6mW total power for DAC playback to headphones 
  • 4 line outputs (single-ended or differential)
  • BTL earpiece driver
  • Digital audio interfaces for multi-processor architecture
    - Asynchronous stereo duplex sample rate conversion
    - Powerful mixing and digital loopback functions 
  • ReTune™ Mobile 5-band, 6-channel parametric EQ
  • Programmable dynamic range controller
  • Dual FLL provides all necessary clocks
    - Self-clocking modes allows processor to sleep
    - All standard sample rates from 8kHz to 96kHz 
  • Active noise reduction circuits
    - DC offset correction removes pops and clicks
    - Ground loop noise cancellation 
  • Integrated LDO regulators
  • 72-ball W-CSP package (4.511mm x 4.023mm x 0.7mm)