WM8741: High Performance Stereo DAC


Description

The WM8741 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 WM8741 also supports DSD bit-stream data format, in both direct DSD and PCM-converted DSD modes. 

The WM8741 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 WM8741 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 WM8741 used with an external digital filter. 

The WM8741 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 WM8741 is available in a convenient 28-SSOP package, and is pin compatible with the WM8740.

Features

  • Advanced Ultra High Performance Multi-bit Sigma-Delta Architecture
    -  128dB SNR (‘A’-weighted mono @ 48kHz)
    -  125dB SNR (‘A’-weighted stereo @ 48kHz)
    -  123dB 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)
    -  DSD mute
  • Hardware or software control modes:
    -  2 and 3 wire serial control interface support
  • Pin compatible with WM8740
  • 4.5V to 5.5V analogue, 3.15V to 3.6V digital supply operation
  • 28-lead SSOP Package