WM8742: Stereo DAC with DSD Support
The WM8742 is a very high performance stereo DAC designed for audio applications such as professional recording systems, A/V receivers and high specification CD, DVD and home theatre systems. The device supports PCM data input word lengths from 16 to 32-bits and sampling rates up to 192kHz. The WM8742 also supports DSD bit-stream data format, in both direct DSD and PCM-converted DSD modes.
The WM8742 includes fine resolution volume and soft mute control, digital de-emphasis and a range of advanced digital filter responses, followed by a digital interpolation filter, multi-bit sigma delta modulator and stereo DAC. Wolfson’s patented architecture optimises the linearity of the DAC and provides maximum insensitivity to clock jitter.
The digital filters include several selectable roll-off and performance characteristics. The user can select between standard sharp or slow roll-off responses. In addition, the WM8742 includes a selection of advanced digital filter characteristics including non-half band filters and minimum phase filters.
This flexibility provides a range of benefits, such as significantly reduced pre-ringing and minimal group delay. The internal digital filters can also be by-passed and the WM8742 used with an external digital filter.
The WM8742 supports two connection schemes for audio DAC control. The 2/3 wire serial control interface provides access to all features. A range of features can also be accessed by hardware control interface.
The WM8742 is available in a convenient 28-SSOP package, and is pin compatible with the WM8740 and WM8741.
- Advanced Ultra High Performance Multi-bit Sigma-Delta Architecture
126dB SNR (‘A’-weighted mono @ 48kHz)
123dB SNR (‘A’-weighted stereo @ 48kHz)
121dB SNR (non-weighted stereo @ 48kHz)
-100dB THD @ 48kHz
Differential analogue voltage outputs
High tolerance to clock jitter
- PCM Mode
Sampling frequency: 32kHz to 192kHz
Input data word length support: 16 to 32-bit
Supports all standard audio interface formats
Selectable advanced digital filter responses
Includes linear/minimum phase and range of tailored characteristics
Enables low pre-ringing, minimal latency
Optional interface to industry standard external filters
Digital volume control in 0.125dB steps with soft ramp and soft mute
Anti-clipping mode to prevent distortion even with input signals recorded up to 0dB
Selectable de-emphasis support
Zero Flag output
- DSD Mode
DSD bit-stream support for SACD applications
Support for normal or phase modulated bit-streams
Direct or PCM converted DSD paths (DSD Plus)
- Hardware or software control modes:
2 and 3 wire serial control interface support
- Pin compatible with WM8740 and WM8741
- 4.5V to 5.5V analogue, 3.15V to 3.6V digital supply operation
- 28-lead SSOP Package
Ordering & Samples
- Specifying the jitter performance of audio components
- An Ultra High Performance DAC with Controlled Time-Domain Response
- Design and evaluation of an audio DAC with non-uniformly weighted dynamic element matching