WM8739 / WM8739L
Stereo Audio ADC
DESCRIPTION
The WM8739 is a stereo audio ADC. The WM8739 is
designed specifically for portable MP3 audio and speech
players and recorders. The WM8739 is also ideal for MD,
CD-RW machines and DAT recorders.
Stereo line-level audio inputs are provided, along with a
mute and volume function, and master or slave mode
clocking schemes. The device also has a programmable
high pass filter to remove residual DC offsets.
Stereo 24-bit multi-bit sigma delta ADCs are used with
oversampling digital interpolation and digital filters. Digital
audio output word lengths from 16-32 bits and sampling
rates from 8KHz to 96KHz are supported.
The device is controlled via a 2 or 3 wire serial interface.
The interface provides access to all features including
volume controls, mutes, de-emphasis and extensive power
management facilities. The device is available in a small 20-
pin SSOP package.
FEATURES
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90dB SNR (‘A’ weighted @ 48kHz) ADC
Low Power
- 12mW all-on, 1.4mW standby (‘L’ version)
- 41mW all-on, 5.3mW standby (standard version)
Low Supply Voltages
- 1.8 – 3.6V Analogue Supply (‘L’ version)
- 2.7 – 3.6V Analogue Supply (standard version)
- 1.42 – 3.6V Digital Supply (both versions)
Input Volume and Mute Controls
ADC Sampling Frequency: 8KHz – 96KHz
Selectable ADC High Pass Filter
2 or 3-Wire MPU Serial Control Interface
Programmable Audio Data Interface Modes
- I
2
S, Left, Right Justified or DSP
- 16/20/24/32 bit Word Lengths
- Master or Slave Clocking Mode
20-Pin SSOP or 5x5mm QFN Package Options
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APPLICATIONS
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CD, Minidisc and DAT Recorders
General Purpose Audio Digitisation
BLOCK DIAGRAM
SDIN
CSB
MODE
SCLK
AVDD
CONTROL INTERFACE
VMID
WM8739
AGND
DIGTAL AUDIO INTERFACE
RLINEIN
VOL/
MUTE
ADC
+12 to -34.5dB,
1.5dB Steps
ADCDAT
ADCLRC
DIGITAL
FILTERS
LLINEIN
VOL/
MUTE
ADC
BCLK
+12 to -34.5dB,
1.5dB Steps
OSC
DIV2
WOLFSON MICROELECTRONICS LTD
www.wolfsonmicro.com
XTI/MCLK
XTO
DCVDD
DBVDD
DGND
Advanced Information, September 2001, Rev 2.2
Copyright
2001
Wolfson Microelectronics Ltd
.