DESCRIPTION
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 two voltage supplies, with all other
internal supply rails generated 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.
Fully differential internal architecture and on-chip RF noise filters
ensure a very high degree of noise immunity. Active ground loop
noise rejection and DC offset correction help prevent pop noise
and suppress ground noise on the headphone outputs.

FEATURES
 Hi-fi 24-bit 4-channel DAC and 2-channel ADC
 100dB SNR during 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 detect & interrupt allows processor to sleep
 2W stereo (2 x 2W) class D/AB speaker driver
 Capless Class W headphone drivers
- Integrated charge pump
- 5.3mW 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
 ReTuneTM Mobile 5-band, 6-channel parametric EQ
 Programmable dynamic range controller
 Dual FLL provides all necessary clocks
- Self-clocking modes allow 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 (4.521 x 4.033 x 0.546mm)

APPLICATIONS
 Smartphones and music phones
 Portable navigation
 Tablets
 eBooks
 Portable Media Players