WM8711
Internet Audio DAC with Integrated Headphone Driver
Product Preview, Novembert 2000, 1.2
DESCRIPTION
FEATURES
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Audio Performance
The WM8711 is a low power stereo DAC with an integrated
headphone driver. The WM8711 is designed specifically for
portable MP3 audio and speech players. The WM8711 is
also ideal for MD, CD machines and DAT players.
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100dB SNR (‘A’ weighted @ 48kHz) DAC
1.42 – 3.6V Digital Supply Operation
2.7 – 3.6V Analogue Supply Operation
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DAC Sampling Frequency: 8KHz – 96KHz
2 or 3-Wire MPU Serial Control Interface
Programmable Audio Data Interface Modes
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Stereo 24-bit multi-bit sigma delta DACs are used with
oversampling digital interpolation filters. Digital audio input
word lengths from 16-32 bits and sampling rates from 8KHz
to 96KHz are supported.
I2S, Left, Right Justified or DSP
16/20/24/32 bit Word Lengths
Master or Slave Clocking Mode
Stereo audio outputs are buffered for driving headphones
from a programmable volume control, line level outputs are
also provided along with anti-thump mute and power
up/down circuitry.
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Stereo Audio Outputs
Output Volume and Mute Controls
Highly Efficient Headphone Driver
Playback Mode Power Consumption < 18mW
28-Pin SSOP Package
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 28-
pin SSOP package.
APPLICATIONS
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Portable MP3 Players
CD and Minidisc Players
A USB mode is provided where all audio rates can be
derived from a single 12MHz MCLK, saving on the need for
a PLL or multiple crystals.
BLOCK DIAGRAM
(21)
(16)
(22) (23)
(24)
(14)
(15)
(8) HPVDD
CONTROL INTERFACE
(11) HPGND
WM8711
(19) RLINEIN
(10) RHPOUT
MUTE
H/P
DRIVER
VOL/
MUTE
+6 to -73dB
1 dB Steps
DAC
DAC
Σ
DACDAT (4)
DACLRC (5)
(13) ROUT
(12) LOUT
DIGITAL
FILTERS
BCLK (3)
+6 to -73dB
1 dB Steps
Σ
VOL/
MUTE
H/P
DRIVER
(9) LHPOUT
(20) LLINEIN
MUTE
CLKIN
DIVIDER
(Div x1, x2)
CLKIN
DIVIDER
(Div x1, x2)
OSC
(26) (25)
(2)
(27)
(1)
(28)
WOLFSON MICROELECTRONICS LTD
Lutton Court, Bernard Terrace, Edinburgh, EH8 9NX, UK
Tel: +44 (0) 131 667 9386
Fax: +44 (0) 131 667 5176
Email: sales@wolfson.co.uk
Product Preview data sheets contain
specifications for products in the formative
phase of development. These products may
be changed or discontinued without notice.
2000 Wolfson Microelectronics Ltd.
http://www.wolfson.co.uk