WM8742
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24-bit 192kHz DAC with Advanced Digital Filtering
DESCRIPTION
FEATURES
Advanced Ultra High Performance Multi-bit Sigma-Delta
Architecture
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.
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
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.
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
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.
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
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.
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
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.
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
The WM8742 is available in
a convenient 28-SSOP
package, and is pin compatible with the WM8740 and
WM8741.
28-lead SSOP Package
APPLICATIONS
Professional audio systems
CD, DVD, SACD audio
Home theatre systems
A/V receivers
WOLFSON MICROELECTRONICS plc
Production Data, February 2013, Rev 4.3
Copyright 2013 Wolfson Microelectronics plc