WM8774
24-bit, 192kHz 8-Channel Input Stereo Codec
DESCRIPTION
FEATURES
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Audio Performance
The WM8774 is a high performance, stereo audio codec
with an 8 channel input selector. The WM8774 is ideal for
surround sound processing applications for home hi-fi,
automotive and other audio visual equipment.
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106dB SNR (‘A’ weighted @ 48kHz) DAC
101dB SNR (‘A’ weighted @ 48kHz) ADC
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•
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DAC Sampling Frequency: 8kHz – 192kHz
ADC Sampling Frequency: 8kHz – 96kHz
3-Wire SPI Compatible Serial Control Interface
Master or Slave Clocking Mode
A stereo 24-bit multi-bit sigma delta ADC is used with an
eight stereo channel input selector. Each channel has
analogue domain mute and programmable gain control.
Digital audio output word lengths from 16-32 bits and
sampling rates from 8kHz to 96kHz are supported.
Programmable Audio Data Interface Modes
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I2S, Left, Right Justified or DSP
A stereo 24-bit multi-bit sigma delta DAC is used with
oversampling digital interpolation filters. Digital audio input
word lengths from 16-32 bits and sampling rates from 8kHz
to 192kHz are supported. Each DAC channel has
independent analogue volume and mute control, with a set
of input multiplexors allowing selection of an external
analogue input into these volume controls.
16/20/24/32 bit Word Lengths
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Stereo DAC with independent analogue and digital volume
controls
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Analogue Bypass Path Feature
Selectable AUX input to the volume controls
Eight stereo ADC inputs with analogue gain adjust from
+19dB to –12dB in 1dB steps
The audio data interface supports I2S, left justified, right
justified and DSP digital audio formats.
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2.7V to 5.5V Analogue, 2.7V to 3.6V Digital supply
Operation
The device is controlled via a 3 wire serial interface. The
interface provides access to all features including channel
selection, volume controls, mutes, de-emphasis and power
management facilities. The device is available in a 64-pin
TQFP package.
5V tolerant digital inputs
APPLICATIONS
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Surround Sound AV Processors and Hi-Fi systems
Automotive Audio
BLOCK DIAGRAM
AIN1L
AIN1R
AIN2L
AIN2R
AIN3L
AIN3R
AIN4L
AIN4R
AUDIO INTERFACE
AND
AIN5L
AIN5R
STEREO
ADC
STEREO
DAC
VOUTL
VOUTR
LOW
PASS
FILTERS
AIN6L
AIN6R
DIGITAL FILTERS
AIN7L
AIN7R
AIN8L
AIN8R
AINOPL
AINOPR
ꢀ
RECL
RECR
CONTROL INTERFACE
MUTE
WM8774
WOLFSON MICROELECTRONICS LTD
Product Preview, June 2002, Rev 1.0
w :: www.wolfsonmicro.com
Copyright 2002 Wolfson Microelectronics Ltd.