WM8722
Stereo DAC with Integrated Tone Generator and
Line/Variable Level Outputs
Advanced Information, May 2000, Rev 1.5
DESCRIPTION
The WM8722 is a high performance stereo DAC designed
for audio applications such as digital TV and set top boxes.
The WM8722 has two stereo analogue outputs, one at line
level and one that includes a digitally controllable mute and
attenuator function. An on-board tone generator can be
routed through the line or variable outputs.
WM8722 supports data input word lengths from 16-24 bits
and sampling rates up to 96kHz. The WM8722 consists of a
serial interface port, digital interpolation filter, multi-bit sigma
delta modulator and stereo DAC in a small 20-pin SSOP
package.
The 3 or 2-wire serial MPU compatible control port provides
access to all features including tone generation, on-chip
mute, attenuation and phase reversal.
The programmable data input port supports glueless
interfaces to popular DSPs, audio decoders and S/PDIF
and AES/EBU receivers.
FEATURES
•
Performance
−
102dB SNR (‘A’ weighted @48kHz)
−
THD+N: -90dB @ F.S.
−
5V or 3V supply operation
−
Sampling frequency: 8kHz – 96kHz
3-wire or 2-wire serial MPU compatible interface for
−
Input data word; 16/20/24-Bit
−
Soft mute
−
De-emphasis
−
Volume control
On-board tone generator (1Hz – 32kHz, 0.1 – 25.5s)
Stereo analogue inputs
20-pin SSOP package
•
•
•
•
APPLICATIONS
•
•
•
Digital TV
Digital broadcast receivers
Set top boxes
BLOCK DIAGRAM
MXINL(14)
+12 to -34.5dB, 1.5dB Steps
4
MONO ATTENUATION CONTROL
+
DIN (17)
BCKIN (19)
LRCIN (18)
SCKI (20)
I2S/SDIF
16,18, 20
OR 24 BITS
DIGITAL
ATTENUATOR
AND
FILTERS
0/-6dB
(13)LINEOUTL
MULTI
BIT
∑∆
MULTI
BIT
SC
DAC
+
0/-6dB
(12) VAROUTL
L Mix Switches (0-9)
R Mix Switches (0-9)
+6 to -73dB,
1dB Steps
MD (3)
MC (2)
LATCH (4)
BUSY (5)
SERIAL
INPUT
INTERFACE
DIGITAL
ATTENUATOR
AND
FILTERS
+
MULTI
BIT
∑∆
MULTI
BIT
SC
DAC
0/-6dB
(9) VAROUTR
+
0/-6dB
(8) LINEOUTR
TCLK (1)
TONE
GENERATOR
TONE
DAC
0 TO -46.5dB, 1.5dB
STEPS
WM8722
+12 TO -34.5dB, 1.5dB
STEPS
(16)
(6)
DVDD DGND
(10)
AGND
(15)
CAP
(11)
(7)
AVDD MXINR
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
http://www.wolfson.co.uk
Advanced Information
data sheets contain
preliminary data on new products in the
preproduction phase of development.
Supplementary data will be published at a
later date.
2000
Wolfson Microelectronics Ltd
.
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
