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)
Ordering & Samples
- Speaker Selection for Class D Output Drivers
- Impedance Compensation (Zobel Network) for Ground Referenced Outputs
- External Component Requirements for Ground Referenced Outputs
- DRC Operation in Wolfson Audio CODECs, Rev 1.0
- Guidelines on How to Use W-CSP Packages and Create Associated PCB Footprints
- I2S USB Audio Streaming, Rev 1.0
- Decoupling and Layout Methodology for Wolfson DACs, ADCs and CODECs, Rev 1.1