WOLFSON WM8772_05

WM8772
w
24-bit, 192kHz 6-Channel Codec with Volume Control
DESCRIPTION
FEATURES
•
The WM8772 is a multi-channel audio codec ideal for DVD
and surround sound processing applications for home hi-fi,
automotive and other audio visual equipment.
Audio Performance
−
•
•
A stereo 24-bit multi-bit sigma delta ADC is used. Digital
audio output word lengths from 16-32 bits and sampling
rates from 32kHz to 96kHz are supported. The 32-lead
version allows separate ADC and DAC samples rates.
•
ADC and DAC can run at different sample rates (32 pin
TQFP version only)
3-Wire SPI Serial or Hardware Control Interface
Programmable Audio Data Interface Modes
•
•
Three 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 192kHz are supported. Each DAC channel has
independent digital volume and mute control.
103dB SNR (‘A’ weighted @ 48kHz) DAC
−
100dB SNR (‘A’ weighted @ 48kHz) ADC (TQFP)
DAC Sampling Frequency: 8kHz – 192kHz
ADC Sampling Frequency: 32kHz – 96kHz
−
−
16/20/24/32 bit Word Lengths
Three Independent stereo DAC outputs with independent
digital volume controls
Master or Slave Audio Data Interface
•
The audio data interface supports I2S, left justified, right
justified and DSP digital audio formats.
•
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 28 lead
SSOP or 32 lead TQFP.
I2S, Left, Right Justified or DSP
•
2.7V to 5.5V Analogue, 2.7V to 3.6V Digital supply
Operation
•
28 lead SSOP or 32 lead TQFP Package
•
•
•
DVD Players
Surround Sound AV Processors and Hi-Fi systems
Automotive Audio
DIN2
DIN3
APPLICATIONS
AGND
AVDD
MCLK
DIN1
LRC
BCLK
DOUT
REFADC
VREFP
VMID
VREFN
BLOCK DIAGRAM - 28 LEAD SSOP
VREFN VREFP
LOW
PASS
FILTER
VOUT1R
STEREO
DAC
LOW
PASS
FILTER
VOUT2R
STEREO
DAC
LOW
PASS
FILTER
VREFN
AINL
AINR
AUDIO
INTERFACE
&
STEREO
ADC
DIGITAL FILTERS
VOUT2L
VOUT3L
VOUT3R
W
WM8772EDS
MD/DM
MC/IWL
ML/I2S
MODE
MUTE
DVDD
DGND
CONTROL INTERFACE
VOUT1L
STEREO
DAC
WOLFSON MICROELECTRONICS plc
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Production Data, October 2005, Rev 4.2
Copyright 2005 Wolfson Microelectronics plc
WM8772
Production Data
AGND
AVDD
ADCMCLK*
DOUT
ADCLRC*
ADCBCLK*
DACBCLK*
DACLRC*
DIN1
DIN2
DIN3
DACMCLK*
ADCVREFN
REFADC
DACVREFP
VMID
DACVREFN
BLOCK DIAGRAM – 32 LEAD TQFP
VREFN VREFP
AINL
AINR
AUDIO
INTERFACE
&
STEREO
ADC
STEREO
DAC
LOW
PASS
FILTER
STEREO
DAC
LOW
PASS
FILTER
STEREO
DAC
LOW
PASS
FILTER
DIGITAL FILTERS
VOUT2L
VOUT2R
VOUT3L
VOUT3R
W
WM8772EFT
MD/DM
MC/IWL
ML/I2S
MODE
MUTE
DVDD
DGND
CONTROL INTERFACE
VOUT1L
VOUT1R
* extra pins on TQFP allow separate
clocking of ADC and DAC
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TABLE OF CONTENTS
DESCRIPTION .......................................................................................................1
FEATURES.............................................................................................................1
APPLICATIONS .....................................................................................................1
BLOCK DIAGRAM - 28 LEAD SSOP ....................................................................1
BLOCK DIAGRAM – 32 LEAD TQFP ....................................................................2
TABLE OF CONTENTS .........................................................................................3
PIN CONFIGURATION - 28 LEAD SSOP .............................................................5
ORDERING INFORMATION ..................................................................................5
PIN CONFIGURATION 32 LEAD TQFP...............................................................6
ORDERING INFORMATION ..................................................................................6
PIN DESCRIPTION – 28 LEAD SSOP...................................................................7
PIN DESCRIPTION – 32 LEAD TQFP ...................................................................8
ABSOLUTE MAXIMUM RATINGS.........................................................................9
RECOMMENDED OPERATING CONDITIONS ...................................................10
ELECTRICAL CHARACTERISTICS ....................................................................10
TERMINOLOGY .......................................................................................................... 12
DIGITAL FILTER CHARACTERISTICS ...............................................................13
DAC FILTER RESPONSES......................................................................................... 13
ADC FILTER RESPONSES......................................................................................... 14
ADC HIGH PASS FILTER ........................................................................................... 14
DIGITAL DE-EMPHASIS CHARACTERISTICS........................................................... 14
WM8772EDS – 28 LEAD SSOP ..........................................................................16
MASTER CLOCK TIMING....................................................................................16
DIGITAL AUDIO INTERFACE – MASTER MODE ....................................................... 16
MPU INTERFACE TIMING .......................................................................................... 19
DEVICE DESCRIPTION.......................................................................................20
INTRODUCTION ......................................................................................................... 20
AUDIO DATA SAMPLING RATES............................................................................... 20
HARDWARE CONTROL MODES ............................................................................... 21
DIGITAL AUDIO INTERFACE ..................................................................................... 23
POWERDOWN MODES ............................................................................................. 28
ZERO DETECT ........................................................................................................... 28
SOFTWARE CONTROL INTERFACE OPERATION................................................... 29
REGISTER MAP - 28 PIN SSOP ........................................................................30
CONTROL INTERFACE REGISTERS ........................................................................ 31
APPLICATIONS INFORMATION .........................................................................39
RECOMMENDED EXTERNAL COMPONENTS .......................................................... 39
SUGGESTED ANALOGUE LOW PASS POST DAC FILTERS ................................... 40
PACKAGE DIMENSIONS ....................................................................................42
WM8722EFT - 32 LEAD TQFP ............................................................................43
MASTER CLOCK TIMING....................................................................................43
DIGITAL AUDIO INTERFACE – MASTER MODE ....................................................... 43
MPU INTERFACE TIMING .......................................................................................... 46
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DEVICE DESCRIPTION.......................................................................................48
INTRODUCTION ......................................................................................................... 48
AUDIO DATA SAMPLING RATES............................................................................... 48
HARDWARE CONTROL MODES ............................................................................... 49
DIGITAL AUDIO INTERFACE ..................................................................................... 51
POWERDOWN MODES ............................................................................................. 57
ZERO DETECT ........................................................................................................... 57
SOFTWARE CONTROL INTERFACE OPERATION................................................... 57
REGISTER MAP – 32 PIN TQFP .........................................................................58
CONTROL INTERFACE REGISTERS ........................................................................ 59
APPLICATIONS INFORMATION .........................................................................69
RECOMMENDED EXTERNAL COMPONENTS .......................................................... 69
SUGGESTED ANALOGUE LOW PASS POST DAC FILTERS ................................... 70
PACKAGE DIMENSIONS ....................................................................................72
IMPORTANT NOTICE ..........................................................................................73
ADDRESS: .................................................................................................................. 73
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PIN CONFIGURATION - 28 LEAD SSOP
MODE
1
28
AVDD
MCLK
2
27
AGND
3
26
VOUT3R
VOUT3L
BCLK
LRC
4
25
DVDD
5
24
VOUT2R
DGND
6
23
VOUT2L
DIN1
7
22
VOUT1R
DIN2
8
21
VOUT1L
DIN3
9
20
AINL
AINR
10
19
ML/I2S
11
18
VMID
MC/IWL
12
17
VREFP
MD/DM
13
16
VREFN
MUTE
14
15
REFADC
DOUT
ORDERING INFORMATION
DEVICE
TEMPERATURE
RANGE
PACKAGE
WM8772SEDS/V
-25 to +85oC
WM8772SEDS/RV
o
-25 to +85 C
MOISTURE
SENSITIVITY LEVEL
PEAK SOLDERING
TEMPERATURE
28-lead SSOP
(Pb free)
MSL3
260oC
28-lead SSOP
(Pb free, tape
and reel)
MSL3
260oC
Note:
Reel quantity = 2,000
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VMID
20 19
AINR
VOUT1L
21
AINL
VOUT2L
24 23 22
VOUT2R
VOUT1R
VOUT3L
PIN CONFIGURATION
32 LEAD TQFP
18 17
DACBCLK
ADCLRC
1
2
3
4
5
6
7
8
DOUT
9
ADCBCLK
DIN3
10
ML/I2S
DACMLCK
DIN1
12 11
31 32
MC/IWL
ADCMCLK
DIN2
15 14 13
29 30
MD/DM
AVDD
MODE
DGND
16
26 27 28
DACVREFN
DVDD
25
DACVREFP
AGND
DACLRC
VOUT3R
ADCVREFN
REFADC
MUTE
ORDERING INFORMATION
DEVICE
TEMPERATURE
RANGE
WM8772SEFT/V
-25 to +85oC
WM8772SEFT/RV
-25 to +85 C
o
MOISTURE SENSITIVITY
LEVEL
PEAK SOLDERING
TEMPERATURE
32-lead TQFP
(Pb free)
MSL2
260oC
32-lead TQFP
(Pb free, tape
and reel)
MSL2
260 C
PACKAGE
o
Note:
Reel quantity = 2,200
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PIN DESCRIPTION – 28 LEAD SSOP
PIN
NAME
TYPE
1
MODE
Digital input
Control format selection
0 = Software control
1 = Hardware control
DESCRIPTION
2
MCLK
Digital input
Master clock; 256, 384, 512 or 768fs (fs = word clock frequency)
(combined ADCMCLK and DACMCLK)
3
BCLK
Digital input/output
Audio interface bit clock (combined ADCBCLK and DACBCLK)
4
LRC
Digital input/output
Audio left/right word clock (combined ADCLRC and DACLRC)
5
DVDD
Supply
Digital positive supply
6
DGND
Supply
Digital negative supply
7
DIN1
Digital input
DAC channel 1 data input
8
DIN2
Digital input
DAC channel 2 data input
9
DIN3
Digital input
DAC channel 3 data input
10
DOUT
Digital output
11
ML/I2S
Digital input
Software Mode: Serial interface Latch signal
Hardware Mode: Input Audio Data Format
12
MC/IWL
Digital input
Software Mode: Serial control interface clock
Hardware Mode: Audio data input word length
13
MD/DM
Digital input
Software Mode: Serial interface data
Hardware Mode: De-emphasis selection
14
MUTE
Digital input/output
DAC Zero Flag output or DAC mute input
15
REFADC
Analogue output
16
VREFN
Supply
ADC and DAC negative supply
17
VREFP
Supply
DAC positive reference supply
18
VMID
Analogue output
19
AINR
Analogue input
ADC right input
20
AINL
Analogue input
ADC left input
21
VOUT1L
Analogue output
DAC channel 1 left output
22
VOUT1R
Analogue output
DAC channel 1 right output
23
VOUT2L
Analogue output
DAC channel 2 left output
24
VOUT2R
Analogue output
DAC channel 2 right output
25
VOUT3L
Analogue output
DAC channel 3 left output
26
VOUT3R
Analogue output
DAC channel 3 right output
27
AGND
Supply
Analogue negative supply and substrate connection
28
AVDD
Supply
Analogue positive supply
ADC data output
ADC reference buffer decoupling pin; 10uF external decoupling
Midrail divider decoupling pin; 10uF external decoupling
Note: Digital input pins have Schmitt trigger input buffers.
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PIN DESCRIPTION – 32 LEAD TQFP
PIN
NAME
TYPE
1
ADCLRC
Digital Input/Output
ADC left/right word clock
DESCRIPTION
2
DACLRC
Digital Input/Output
DAC left/right word clock
3
DVDD
Supply
Digital positive supply
4
DGND
Supply
Digital negative supply
5
DIN1
Digital Input
DAC channel 1 data input
6
DIN2
Digital Input
DAC channel 2 data input
7
DIN3
Digital Input
DAC channel 3 data input
8
DOUT
Digital Output
9
ML/I2S
Digital Input
Software Mode: Serial interface Latch signal
Hardware Mode: Input Audio Data Format
10
MC/IWL
Digital Input
Software Mode: Serial control interface clock
Hardware Mode: Audio data input word length
11
MD/DM
Digital Input
Software Mode: Serial interface data
Hardware Mode: De-emphasis selection
12
MUTE
Digital Input/Output
DAC Zero Flag output or DAC Mute Input
13
REFADC
Analogue Output
14
ADCVREFN
Supply
ADC negative supply
15
DACVREFN
Supply
DAC negative supply
16
DACVREFP
Supply
17
VMID
Analogue Output
18
AINR
Analogue Input
ADC right input
19
AINL
Analogue Input
ADC left input
20
VOUT1L
Analogue Output
DAC channel 1 left output
21
VOUT1R
Analogue Output
DAC channel 1 right output
22
VOUT2L
Analogue Output
DAC channel 2 left output
23
VOUT2R
Analogue Output
DAC channel 2 right output
24
VOUT3L
Analogue Output
DAC channel 3 left output
25
VOUT3R
Analogue Output
DAC channel 3 right output
26
AGND
Supply
Analogue negative supply and substrate connection
27
AVDD
Supply
Analogue positive supply
28
MODE
Digital Input
Control format selection
0 = Software control
1 = Hardware control
29
ADCMCLK
Digital Input
Master ADC clock; 256, 384, 512 or 768fs (fs = word clock frequency)
30
DACMCLK
Digital Input
Master DAC clock; 256, 384, 512 or 768fs (fs = word clock frequency)
31
ADCBCLK
Digital Input/Output
ADC audio interface bit clock
32
DACBCLK
Digital Input/Output
DAC audio interface bit clock
ADC data output
ADC reference buffer decoupling pin; 10uF external decoupling
DAC positive reference supply
Midrail divider decoupling pin; 10uF external decoupling
Note: Digital input pins have Schmitt trigger input buffers.
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ABSOLUTE MAXIMUM RATINGS
Absolute Maximum Ratings are stress ratings only. Permanent damage to the device may be caused by continuously operating at
or beyond these limits. Device functional operating limits and guaranteed performance specifications are given under Electrical
Characteristics at the test conditions specified.
ESD Sensitive Device. This device is manufactured on a CMOS process. It is therefore generically susceptible
to damage from excessive static voltages. Proper ESD precautions must be taken during handling and storage
of this device.
Wolfson tests its package types according to IPC/JEDEC J-STD-020B for Moisture Sensitivity to determine acceptable storage
conditions prior to surface mount assembly. These levels are:
MSL1 = unlimited floor life at <30°C / 85% Relative Humidity. Not normally stored in moisture barrier bag.
MSL2 = out of bag storage for 1 year at <30°C / 60% Relative Humidity. Supplied in moisture barrier bag.
MSL3 = out of bag storage for 168 hours at <30°C / 60% Relative Humidity. Supplied in moisture barrier bag.
The Moisture Sensitivity Level for each package type is specified in Ordering Information.
CONDITION
Digital supply voltage
Analogue supply voltage
MIN
MAX
-0.3V
+5V
-0.3V
+7V
Voltage range digital inputs 1
DGND -0.3V
DVDD +0.3V
Voltage range analogue inputs 1
AGND -0.3V
AVDD +0.3V
Master Clock Frequency
37MHz
Operating temperature range, TA
-25°C
+85°C
Storage temperature after soldering
-65°C
+150°C
Package body temperature (soldering 10 seconds)
Package body temperature (soldering 2 minutes)
Refer to Ordering
Information, p5 and p6
+183°C
Notes:
1.
Analogue and digital grounds must always be within 0.3V of each other.
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RECOMMENDED OPERATING CONDITIONS
PARAMETER
SYMBOL
Digital supply range
Analogue supply range
Ground
MAX
UNIT
DVDD
TEST CONDITIONS
MIN
2.7
TYP
3.6
V
AVDD, VREFP
2.7
5.5
V
+0.3
V
AGND, VREFN, DGND
0
Difference DGND to AGND
-0.3
0
V
Note: Digital supply DVDD must never be more than 0.3V greater than AVDD.
ELECTRICAL CHARACTERISTICS
Test Conditions
AVDD, VREFP = 5V, DVDD = 3.3V, AGND, VREFN = 0V, DGND = 0V, TA = +25oC, fs = 48kHz, MCLK = 256fs, 32-pin TQFP
version unless otherwise stated. ADC/DAC in Slave Mode unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
DAC Performance (Load = 10kΩ, 50pF)
0dBFs Full scale output voltage
1.0 x
VREFP/5
Vrms
103
dB
SNR (Note 1,2,4)
A-weighted,
@ fs = 48kHz
SNR (Note 1,2,4)
A-weighted
@ fs = 96kHz
102
dB
SNR (Note 1,2,4)
A-weighted
@ fs = 192kHz
101
dB
SNR (Note 1,2,4)
A-weighted
@ fs = 48kHz, AVDD =
3.3V
99
dB
SNR (Note 1,2,4)
A-weighted
@ fs = 96kHz, AVDD =
3.3V
99
dB
103
dB
Dynamic Range (Note 2,4)
DNR
Total Harmonic Distortion (THD)
Mute Attenuation
A-weighted, -60dB full
scale input
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PSRR
90
1kHz, 0dB.Fs
-90
1kHz Input, 0dB gain
100
dB
100
dB
1kHz 100mVp-p
50
dB
20Hz to 20kHz
100mVp-p
45
dB
DAC channel separation
Power Supply Rejection Ratio
95
-80
dB
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Test Conditions
AVDD, VREFP = 5V, DVDD = 3.3V, AGND, VREFN = 0V, DGND = 0V, TA = +25oC, fs = 48kHz, MCLK = 256fs, 32-pin TQFP
version unless otherwise stated. ADC/DAC in Slave Mode unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
ADC Performance
Input Signal Level (0dB)
2.0 x
REFADC/5
Vrms
Input resistance
20
kΩ
Input capacitance
10
pF
100
dB
SNR (Note 1,2,4)
A-weighted, 0dB gain
@ fs = 48kHz
SNR (Note 1,2,4)
A-weighted, 0dB gain
@ fs = 96kHz
64 x OSR
100
dB
SNR (Note 1,2,4)
A-weighted, 0dB gain
@ fs = 48kHz, AVDD =
3.3V
93
dB
SNR (Note 1,2,4)
A-weighted, 0dB gain
@ fs = 96kHz, AVDD
= 3.3V
64 x OSR
93
dB
Total Harmonic Distortion (THD)
ADC Channel Separation
Mute Attenuation
Power Supply Rejection Ratio
PSRR
80
kHz, 0dBFs
-80
dB
1kHz, -1dBFs
-82
dB
dB
1kHz Input
90
1kHz Input, 0dB gain
90
dB
1kHz 100mVpp
50
dB
20Hz to 20kHz
100mVpp
45
dB
Digital Logic Levels (CMOS Levels)
Input LOW level
VIL
Input HIGH level
VIH
0.3 x DVDD
0.7 x DVDD
Input leakage current
±0.2
Input capacitance
±1
5
Output LOW
VOL
IOL=1mA
Output HIGH
VOH
IOH= -1mA
V
V
µA
pF
0.1 x DVDD
0.9 x DVDD
V
V
Analogue Reference Levels
Reference voltage
VVMID
Potential divider resistance
RVMID
VREFP/2 –
50mV
VREFP to VMID and
VMID to VREFN
VREFP/2
VREFP/2 +
50mV
50
V
kΩ
Supply Current
Analogue supply current
Digital supply current
AVDD, VREFP = 5V
45
mA
DVDD = 3.3V
16
mA
Notes:
1.
Ratio of output level with 1kHz full scale input, to the output level with all zeros into the digital input, measured ‘A’
weighted.
2.
All performance measurements done with 20kHz low pass filter, and where noted an A-weight filter. Failure to use
such a filter will result in higher THD+N and lower SNR and Dynamic Range readings than are found in the Electrical
Characteristics. The low pass filter removes out of band noise; although it is not audible it may affect dynamic
specification values.
3.
VMID decoupled with 10uF and 0.1uF capacitors (smaller values may result in reduced performance).
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TERMINOLOGY
1.
Signal-to-noise ratio (dB) - SNR is a measure of the difference in level between the full scale output and the output
with no signal applied. (No Auto-zero or Automute function is employed in achieving these results).
2.
Dynamic range (dB) - DNR is a measure of the difference between the highest and lowest portions of a signal.
Normally a THD+N measurement at 60dB below full scale. The measured signal is then corrected by adding the 60dB
to it. (e.g. THD+N @ -60dB= -32dB, DR= 92dB).
3.
THD+N (dB) - THD+N is a ratio, of the rms values, of (Noise + Distortion)/Signal.
4.
Stop band attenuation (dB) - Is the degree to which the frequency spectrum is attenuated (outside audio band).
5.
Channel Separation (dB) - Also known as Cross-Talk. This is a measure of the amount one channel is isolated from
the other. Normally measured by sending a full scale signal down one channel and measuring the other.
6.
Pass-Band Ripple - Any variation of the frequency response in the pass-band region.
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DIGITAL FILTER CHARACTERISTICS
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
ADC Filter
±0.01 dB
Passband
0
0.4535fs
-6dB
0.5fs
±0.01
Passband ripple
Stopband
dB
0.5465fs
Stopband Attenuation
f > 0.5465fs
-65
dB
DAC Filter
±0.05 dB
Passband
0.444fs
-3dB
0.487fs
±0.05
Passband ripple
Stopband
dB
0.555fs
Stopband Attenuation
f > 0.555fs
-60
dB
Table 1 Digital Filter Characteristics
DAC FILTER RESPONSES
0.2
0
0.15
-20
Response (dB)
Response (dB)
0.1
-40
-60
0.05
0
-0.05
-80
-0.1
-100
-0.15
-120
-0.2
0
0.5
1
1.5
Frequency (Fs)
2
2.5
3
Figure 1 DAC Digital Filter Frequency Response
– 44.1, 48 and 96KHz
0
0.05
0.1
0.15
0.2
0.25
0.3
Frequency (Fs)
0.35
0.4
0.45
0.5
Figure 2 DAC Digital Filter Ripple –44.1, 48 and 96kHz
0.2
0
0
-0.2
Response (dB)
Response (dB)
-20
-40
-0.4
-0.6
-60
-0.8
-80
-1
0
0.2
0.4
0.6
Frequency (Fs)
0.8
Figure 3 DAC Digital Filter Frequency Response
– 192KHz
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1
0
0.05
0.1
0.15
0.2
0.25
0.3
Frequency (Fs)
0.35
0.4
0.45
0.5
Figure 4 DAC Digital Filter Ripple – 192kHz
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ADC FILTER RESPONSES
0.02
0
0.015
0.01
Response (dB)
Response (dB)
-20
-40
0.005
0
-0.005
-60
-0.01
-0.015
-80
-0.02
0
0.5
1
1.5
Frequency (Fs)
2
2.5
3
Figure 5 ADC Digital Filter Frequency Response
0
0.05
0.1
0.15
0.2
0.25
0.3
Frequency (Fs)
0.35
0.4
0.45
0.5
Figure 6 ADC Digital Filter Ripple
ADC HIGH PASS FILTER
The WM8772EDS has a selectable digital high pass filter to remove DC offsets. The filter response is characterised by the
following polynomial.
H ( z) =
1 − z −1
1 − 0.9995z −1
DIGITAL DE-EMPHASIS CHARACTERISTICS
0
1
0.5
-2
Response (dB)
Response (dB)
0
-4
-6
-0.5
-1
-1.5
-2
-8
-2.5
-10
-3
0
2
4
6
8
10
Frequency (kHz)
12
14
Figure 7 De-Emphasis Frequency Response (32kHz)
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16
0
2
4
6
8
10
Frequency (kHz)
12
14
16
Figure 8 De-Emphasis Error (32KHz)
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0
0.4
0.3
-2
Response (dB)
Response (dB)
0.2
-4
-6
0.1
0
-0.1
-0.2
-8
-0.3
-10
-0.4
0
5
10
Frequency (kHz)
15
20
Figure 9 De-Emphasis Frequency Response (44.1KHz)
0
5
10
Frequency (kHz)
15
20
Figure 10 De-Emphasis Error (44.1KHz)
0
1
0.8
-2
0.6
Response (dB)
Response (dB)
0.4
-4
-6
0.2
0
-0.2
-0.4
-8
-0.6
-0.8
-10
-1
0
5
10
15
Frequency (kHz)
20
Figure 11 De-Emphasis Frequency Response (48kHz)
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0
5
10
15
Frequency (kHz)
20
Figure 12 De-Emphasis Error (48kHz)
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PAGES 12 TO 36 DESCRIBE THE OPERATION OF THE WM8772EDS
28 LEAD SSOP PRODUCT VARIANT.
PAGES 37 TO 66 DESCRIBE THE OPERATION OF THE WM8772EFT
32 LEAD TQFP PRODUCT VARIANT.
WM8772EDS – 28 LEAD SSOP
MASTER CLOCK TIMING
t MCLKL
MCLK
tMCLKH
t MCLKY
Figure 13 ADC and DAC Master Clock Timing Requirements
Test Conditions
AVDD, VREFP = 5V, DVDD = 3.3V, AGND, VREFN = 0V, AGND, DGND = 0V, TA = +25oC, fs = 48kHz, DACMCLK and
ADCMCLK = 256fs unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
System Clock Timing Information
MCLK System clock pulse width
high
tMCLKH
11
ns
MCLK System clock pulse width
low
tMCLKL
11
ns
MCLK System clock cycle time
tMCLKY
28
MCLK Duty cycle
40:60
ns
60:40
Table 2 Master Clock Timing Requirements
DIGITAL AUDIO INTERFACE – MASTER MODE
BCLK
LRC
DSP/
ENCODER/
DECODER
WM8772
CODEC
DOUT
DIN1/2/3
3
Figure 14 Audio Interface - Master Mode
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BCLK
(Output)
tDL
LRC
(Output)
tDDA
DOUT
DIN1/2/3
tDST
tDHT
Figure 15 Digital Audio Data Timing – Master Mode
Test Conditions
AVDD, VREFP = 5V, DVDD = 3.3V, AGND, VREFN, DGND = 0V, TA = +25oC, Master Mode, fs = 48kHz, MCLK = 256fs unless
otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Audio Data Input Timing Information
LRC propagation delay from
BCLK falling edge
tDL
0
10
ns
DOUT propagation delay
from BCLK falling edge
tDDA
0
10
ns
DIN1/2/3 setup time to
BCLK rising edge
tDST
10
ns
DIN1/2/3 hold time from
BCLK rising edge
tDHT
10
ns
Table 3 Digital Audio Data Timing – Master Mode
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DIGITAL AUDIO INTERFACE – SLAVE MODE
LRC
BCLK
WM8772
CODEC
DSP
ENCODER/
DECODER
DOUT
DIN1/2/3
3
Figure 16 Audio Interface – Slave Mode
tBCH
tBCL
BCLK
tBCY
LRC
tDS
tLRH
tLRSU
DIN1/2/3
tDD
tDH
DOUT
Figure 17 Digital Audio Data Timing – Slave Mode
Test Conditions
AVDD = 5V, DVDD = 3.3V, AGND = 0V, DGND = 0V, TA = +25oC, Slave Mode, fs = 48kHz, MCLK = 256fs unless otherwise
stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Audio Data Input Timing Information
BCLK cycle time
tBCY
50
ns
BCLK pulse width high
tBCH
20
ns
BCLK pulse width low
tBCL
20
ns
LRC set-up time to BCLK
rising edge
tLRSU
10
ns
LRC hold time from BCLK
rising edge
tLRH
10
ns
DIN1/2/3 set-up time to
BCLK rising edge
tDS
10
ns
DIN1/2/3 hold time from
BCLK rising edge
tDH
10
ns
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Test Conditions
AVDD = 5V, DVDD = 3.3V, AGND = 0V, DGND = 0V, TA = +25oC, Slave Mode, fs = 48kHz, MCLK = 256fs unless otherwise
stated.
PARAMETER
SYMBOL
DOUT propagation delay
from BCLK falling edge
TEST CONDITIONS
MIN
tDD
TYP
0
MAX
UNIT
10
ns
Table 4 Digital Audio Data Timing – Slave Mode
MPU INTERFACE TIMING
tCSL
tCSH
ML/I2S
tSCY
tCSS
tSCS
tSCL
tSCH
MC/IWL
MD/DM
LSB
tDSU
tDHO
Figure 18 SPI Compatible Control Interface Input Timing
Test Conditions
AVDD = 5V, DVDD = 3.3V, AGND, DGND = 0V, TA = +25oC, fs = 48kHz, DACMCLK and ADCMCLK = 256fs unless otherwise
stated
PARAMETER
SYMBOL
MIN
TYP
MAX
UNIT
MC/IWL rising edge to ML/I2S rising edge
tSCS
60
ns
MC/IWL pulse cycle time
tSCY
80
ns
MC/IWL pulse width low
tSCL
30
ns
MC/IWL pulse width high
tSCH
30
ns
MD/DM to MC/IWL set-up time
tDSU
20
ns
MC/IWL to MD/DM hold time
tDHO
20
ns
ML/I2S pulse width low
tCSL
20
ns
ML/I2S pulse width high
tCSH
20
ns
ML/I2S rising to MC/IWL rising
tCSS
20
ns
Table 5 3-Wire SPI Compatible Control Interface Input Timing Information
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DEVICE DESCRIPTION
INTRODUCTION
WM8772EDS is a complete 6-channel DAC, 2-channel ADC audio codec, including digital
interpolation and decimation filters, multi-bit sigma delta stereo ADC, and switched capacitor multibit sigma delta DACs with digital volume controls on each channel and output smoothing filters.
The device is implemented as three separate stereo DACs and a stereo ADC in a single package
and controlled by a single interface.
Each stereo DAC has its own data input DIN1/2/3, the stereo ADC has it’s own data output DOUT.
The word clock LRC, bit clock BCLK and master clock MCLK are shared between them.
The Audio Interface may be configured to operate in either master or slave mode. In Slave mode
LRC and BCLK are all inputs. In Master mode LRC and BCLK are all outputs.
Each DAC has its own digital volume control that is adjustable in 0.5dB steps. The digital volume
controls may be operated independently. In addition, a zero cross detect circuit is provided for each
DAC for the digital volume controls. The digital volume control detects a transition through the zero
point before updating the volume. This minimises audible clicks and ‘zipper’ noise as the gain values
change.
Control of internal functionality of the device is by 3-wire serial or pin programmable control interface.
The software control interface may be asynchronous to the audio data interface as control data will
be re-synchronised to the audio processing internally.
Operation using master clocks of 128fs, 192fs, 256fs, 384fs, 512fs or 768fs is provided for the DAC,
for operation of both the ADC and DAC master clocks of 256fs, 384fs, 512fs and 768fs is provided.
In Slave mode selection between clock rates is automatically controlled. In master mode, the sample
rate is set by control bits RATE. Audio sample rates (fs) from less than 8ks/s up to 192ks/s are
allowed for the DAC and from less than 32ks/s up to 96ks/s for the ADC, provided the appropriate
master clock is input.
The audio data interface supports right, left and I2S interface formats along with a highly flexible DSP
serial port interface.
AUDIO DATA SAMPLING RATES
In a typical digital audio system there is only one central clock source producing a reference clock to
which all audio data processing is synchronised. This clock is often referred to as the audio system’s
Master Clock. The external master system clock can be applied directly through the MCLK input pin
with no software configuration necessary. In a system where there are a number of possible sources
for the reference clock it is recommended that the clock source with the lowest jitter be used to
optimise the performance of the ADC and DAC.
The master clock for WM8772EDS supports audio sampling rates from 128fs to 768fs, where fs is
the audio sampling frequency (LRC) typically 32kHz, 44.1kHz, 48kHz, 96kHz or 192kHz (for DAC
operation only). For ADC operation sample rates from 256fs to 768fs are supported. The master
clock is used to operate the digital filters and the noise shaping circuits.
In Slave mode the WM8772EDS has a master clock detection circuit that automatically determines
the relationship between the system clock frequency and the sampling rate (to within +/- 32 master
clocks). If there is a greater than 32 clocks error the interface defaults to 768fs mode. The master
clocks must be synchronised with LRC, although the WM8772EDS is tolerant of phase variations or
jitter on this clock. Table 6 shows the typical master clock frequency inputs for the WM8772EDS.
The signal processing for the WM8772EDS typically operates at an oversampling rate of 128fs for
both ADC and DAC. The exception to this for the DAC is for operation with a 128/192fs system clock,
e.g. for 192kHz operation, when the oversampling rate is 64fs. For ADC operation at 96kHz it is
recommended that the user set the ADCOSR bit. This changes the ADC signal processing
oversample rate to 64fs.
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SAMPLING
RATE
(LRC)
System Clock Frequency (MHz)
128fs
192fs
256fs
384fs
512fs
768fs
32kHz
4.096
6.144
8.192
12.288
16.384
24.576
44.1kHz
5.6448
8.467
11.2896
16.9340
22.5792
33.8688
24.576
36.864
48kHz
6.144
9.216
12.288
18.432
96kHz
12.288
18.432
24.576
36.864
192kHz
24.576
36.864
Unavailable Unavailable
Unavailable Unavailable Unavailable Unavailable
Table 6 System Clock Frequencies Versus Sampling Rate
(ADC does not support 128fs and 192fs)
HARDWARE CONTROL MODES
When the MODE pin is held high, the following hardware modes of operation are available.
Note: When in hardware mode the ADC and DAC will only run in slave mode.
MUTE AND AUTOMUTE OPERATION
In both hardware and software modes, MUTE controls the selection of MUTE directly, and can be
used to enable and disable the automute function. This pin becomes an output when left floating and
indicates infinite ZERO detect (IZD) has been detected.
DESCRIPTION
0
1
Floating
Normal Operation
Mute DAC channels
Enable IZD, MUTE becomes an output to indicate when IZD occurs.
L=IZD detected, H=IZD not detected.
Table 7 Mute and Automute Control
Figure 19 shows the application and release of MUTE whilst a full amplitude sinusoid is being played
at 48kHz sampling rate. When MUTE (lower trace) is asserted, the output (upper trace) begins to
decay exponentially from the DC level of the last input sample. The output will decay towards VMID
with a time constant of approximately 64 input samples. If MUTE is applied to all channels for 1024
or more input samples the outputs will be connected directly to VMID if IZD is set. When MUTE is deasserted, the output will restart immediately from the current input sample.
1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
0
0.001
0.002
0.003
0.004
0.005
0.006
Time(s)
Figure 19 Application and Release of Soft Mute
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The MUTE pin is an input to select mute or not mute. MUTE is active high; taking the pin high causes
the filters to soft mute, ramping down the audio signal over a few milliseconds. Taking MUTE low
again allows data into the filter.
The automute function detects a series of ZERO value audio samples of 1024 samples long being
applied to both channels. After such an event, a latch is set whose output (AUTOMUTED) is wire
OR’ed through a 10kΩ resistor to the MUTE pin. Thus if the MUTE pin is not being driven, the
automute function will assert mute.
If MUTE is tied low, AUTOMUTED is overridden and will not mute unless the IZD register bit is set. If
MUTE is driven from a bi-directional source, then both MUTE and automute functions are available. If
MUTE is not driven, AUTOMUTED appears as a weak output (10kΩ source impedance) and can be
used to drive external mute circuits. AUTOMUTED will be removed as soon as any channel receives
a non-ZERO input.
A diagram showing how the various Mute modes interact is shown below Figure 20.
IZD (Register Bit)
AUTOMUTED
(Internal Signal)
10kΩ
Ω
SOFTMUTE
(Internal
Signal)
MUTE
PIN
MUTE (Register Bit)
Figure 20 Selection Logic for MUTE Modes
INPUT FORMAT SELECTION
In hardware mode, ML/I2S and MC/IWL become input controls for selection of input data format type
and input data word length for both the ADC and DAC.
ML/I2S
MC/IWL
INPUT DATA MODE
0
0
24-bit right justified
0
1
20-bit right justified
1
0
16-bit I2S
1
1
24-bit I2S
Table 8 Input Format Selection
Note:
In 24 bit I2S mode, any width of 24 bits or less is supported provided that the left/right clocks (LRC)
are high for a minimum of 24 bit clocks (BCLK) and low for a minimum of 24 bit clocks.
DE-EMPHASIS CONTROL
In hardware mode, the MD/DM pin becomes an input control for selection of de-emphasis filtering to
be applied.
MD/DM
DE-EMPHASIS
0
Off
1
On
Table 9 De-emphasis Control
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DIGITAL AUDIO INTERFACE
MASTER AND SLAVE MODES
The audio interface operates in either Slave or Master mode, selectable using the MS control bit. In
both Master and Slave modes DIN1/2/3 are always inputs to the WM8772EDS and DOUT is always
an output. The default is Slave mode.
In Slave mode, LRC and BCLK are inputs to the WM8772EDS (Figure 21). DIN1/2/3 and LRC are
sampled by the WM8772EDS on the rising edge of BCLK. ADC data is output on DOUT and
changes on the falling edge of BCLK.
By setting the control bit BCP the polarity of BCLK may be reversed so that DIN1/2/3 and LRC are
sampled on the falling edge of BCLK and DOUT changes on the rising edge of BCLK.
LRC
WM8772
CODEC
BCLK
DSP
ENCODER/
DECODER
DOUT
DIN1/2/3
3
Figure 21 Slave Mode
In Master mode, LRC and BCLK are outputs from the WM8772EDS (Figure 22). LRC and BCLK are
generated by the WM8772EDS. DIN1/2/3 are sampled by the WM8772EDS on the rising edge of
BCLK so the controller must output DAC data that changes on the falling edge of BCLK. ADC data is
output on DOUT and changes on the falling edge of BCLK.
By setting control bit BCP the polarity of BCLK may be reversed so that DIN1/2/3 are sampled on the
falling edge of BCLK, and DOUT changes on the rising edge of BCLK.
BCLK
WM8772
CODEC
DSP/
ENCODER/
DECODER
LRC
DOUT
DIN1/2/3
3
Figure 22 Master Mode
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AUDIO INTERFACE FORMATS
Audio data is applied to the internal DAC filters, or output from the ADC filters, via the Digital Audio
Interface. 5 popular interface formats are supported:
•
Left Justified mode
•
Right Justified mode
•
I2S mode
•
DSP mode A
•
DSP mode B
All 5 formats send the MSB first and support word lengths of 16, 20, 24 and 32 bits, with the
exception of 32 bit right justified mode, which is not supported.
In left justified, right justified and I2S modes, the digital audio interface receives DAC data on the
DIN1/2/3 inputs and outputs ADC data on DOUT. Audio Data for each stereo channel is time
multiplexed with LRC indicating whether the left or right channel is present. LRC is also used as a
timing reference to indicate the beginning or end of the data words.
In left justified, right justified and I2S modes, the minimum number of BCLKs per LRC period is 2
times the selected word length. LRC must be high for a minimum of word length BCLKs and low for a
minimum of word length BCLKs. Any mark to space ratio on LRC is acceptable provided the above
requirements are met.
In DSP mode A or Mode B, all 6 DAC channels are time multiplexed onto DIN1. LRC is used as a
frame sync signal to identify the MSB of the first word. The minimum number of BCLKs per LRC
period is 6 times the selected word length. Any mark to space ratio is acceptable on LRC provided
the rising edge is correctly positioned. The ADC data may also be output in DSP mode A or mode B,
with LRC used as a frame sync to identify the MSB of the first word. The minimum number of BCLKs
per LRC period is 2 times the selected word length if only the ADC is being operated.
LEFT JUSTIFIED MODE
In left justified mode, the MSB of DIN1/2/3 is sampled by the WM8772EDS on the first rising edge of
BCLK following a LRC transition. The MSB of the ADC data is output on DOUT and changes on the
same falling edge of BCLK as LRC and may be sampled on the rising edge of BCLK. LRC is high
during the left samples and low during the right samples (Figure 23).
1/fs
LEFT CHANNEL
RIGHT CHANNEL
DACLRC/
ADCLRC
DACBCLK/
ADCBCLK
DIN1/2/3/
DOUT
1
MSB
2
3
n-2 n-1
n
LSB
1
MSB
2
3
n-2 n-1
n
LSB
Figure 23 Left Justified Mode Timing Diagram
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RIGHT JUSTIFIED MODE
In right justified mode, the LSB of DIN1/2/3 is sampled by the WM8772EDS on the rising edge of
BCLK preceding a LRC transition. The LSB of the ADC data is output on DOUT and changes on the
falling edge of BCLK preceding a LRC transition and may be sampled on the rising edge of BCLK.
LRC are high during the left samples and low during the right samples (Figure 24).
1/fs
LEFT CHANNEL
RIGHT CHANNEL
DACLRC/
ADCLRC
DACBCLK/
ADCBCLK
DIN1/2/3/
DOUT
1
2
3
n-2 n-1
MSB
n
1
LSB
2
3
n-2 n-1
MSB
n
LSB
Figure 24 Right Justified Mode Timing Diagram
2
I S MODE
In I2S mode, the MSB of DIN1/2/3 is sampled by the WM8772EDS on the second rising edge of
BCLK following a LRC transition. The MSB of the ADC data is output on DOUT and changes on the
first falling edge of BCLK following an LRC transition and may be sampled on the rising edge of
BCLK. LRC are low during the left samples and high during the right samples.
1/fs
LEFT CHANNEL
RIGHT CHANNEL
DACLRC/
ADCLRC
DACBCLK/
ADCBCLK
1 BCLK
1 BCLK
DIN1/2/3/
DOUT
1
2
3
MSB
n-2 n-1
n
LSB
1
MSB
2
3
n-2 n-1
n
LSB
Figure 25 I2S Mode Timing Diagram
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DSP MODE A
In DSP mode A, the MSB of DAC channel 1 left data is sampled by the WM8772EDS on the second
rising edge on BCLK following a LRC rising edge. DAC channel 1 right and DAC channels 2 and 3
data follow DAC channel 1 left data (Figure 26).
Figure 26 DSP Mode Audio Interface - Mode A Slave, DAC
1 BCLK
1 BCLK
1/fs
DACLRC
DACBCLK
CHANNEL 1
LEFT
DIN1
1
2
MSB
CHANNEL 1
RIGHT
n
n-1
1
2
n-1 n
CHANNEL 2
LEFT
1
2
CHANNEL 3
RIGHT
n-1
NO VALID DATA
n
LSB
Input Word Length (IWL)
Figure 27 DSP Mode Audio Interface - Mode A Master, DAC
The MSB of the left channel ADC data is output on DOUT and changes on the first falling edge of
BCLK following a low to high LRC transition and may be sampled on the rising edge of BCLK. The
right channel ADC data is contiguous with the left channel data (Figure 26)
Figure 28 DSP Mode Audio Interface - Mode A Slave, ADC
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1 BCLK
1 BCLK
1/fs
ADCLRC
ADCBCLK
LEFT CHANNEL
DOUT
1
2
RIGHT CHANNEL
n
n-1
MSB
1
2
n-1
NO VALID DATA
n
LSB
Input Word Length (IWL)
Figure 29 DSP Mode Audio Interface - Mode A Master, ADC
DSP MODE B
In DSP mode B, the MSB of DAC channel 1 left data is sampled by the WM8772EDS on the first
BCLK rising edge following a LRC rising edge. DAC channel 1 right and DAC channels 2 and 3 data
follow DAC channel 1 left data (Figure 30).
Figure 30 DSP Mode Audio Interface - Mode B Slave, DAC
1/fs
DACLRC
DACBCLK
CHANNEL 1
LEFT
DIN1
1
2
MSB
CHANNEL 1
RIGHT
n
n-1
1
2
n-1
CHANNEL 2
LEFT
n
1
2
CHANNEL 3
RIGHT
n-1
n
NO VALID DATA
1
LSB
Input Word Length (IWL)
Figure 31 DSP Mode Audio Interface - Mode B Master, DAC
The MSB of the left channel ADC data is output on DOUT and changes on the same falling edge of
BCLK as the low to high LRC transition and may be sampled on the rising edge of BCLK. The right
channel ADC data is contiguous with the left channel data (Figure 32).
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Figure 32 DSP Mode Audio Interface - Mode B Slave, ADC
1/fs
ADCLRC
BCK
LEFT CHANNEL
1
DOUT
2
MSB
RIGHT CHANNEL
n
n-1
1
2
n-1
NO VALID DATA
n
1
LSB
Input Word Length (IWL)
Figure 33 DSP Mode Audio Interface - Mode B Master, ADC
In both DSP mode A and mode B, DACL1 is always sent first, followed immediately by DACR1 and
the data words for the other 6 channels. No BCLK edges are allowed between the data words. The
word order is DAC1 left, DAC1 right, DAC2 left, DAC2 right, DAC3 left, DAC3 right.
POWERDOWN MODES
The WM8772EDS has powerdown control bits allowing specific parts of the WM8772EDS to be
powered off when not being used. Control bit ADCPD powers off the ADC. The three stereo DACs
each have a separate powerdown control bit, DACPD[2:0] allowing individual stereo DACs to be
powered off when not in use. Setting ADCPD and DACPD[2:0] will powerdown everything except the
references VMID and REFADC. These may be powered down by setting PDWN. Setting PDWN will
override all other powerdown control bits. It is recommended that the ADC and DACs are powered
down before setting PDWN.
ZERO DETECT
The WM8772EDS has a zero detect circuit for each DAC channel that detects when 1024
consecutive zero samples have been input. The MUTE pin output may be programmed to output the
zero detect signal (see Table 10) which may then be used to control external muting circuits. A ‘1’ on
MUTE indicates a zero detect. The zero detect may also be used to automatically enable DAC mute
by setting IZD.
DZFM[1:0]
MUTE
00
All channels zero
01
Channel 1 zero
10
Channel 2 zero
11
Channel 3 zero
Table 10 Zero Flag Output Select
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SOFTWARE CONTROL INTERFACE OPERATION
The WM8772EDS is controlled using a 3-wire serial interface in software mode or pin
programmable in hardware mode.
The control mode is selected by the state of the MODE pin.
3-WIRE (SPI COMPATIBLE) SERIAL CONTROL MODE
MD/DM is used for the program data, MC/IWL is used to clock in the program data and ML/I2S is
used to latch the program data. MD/DM is sampled on the rising edge of MC/IWL. The 3-wire
interface protocol is shown in Figure 34.
ML/I2S
MC/IWL
MD/DM
B15
B14
B13
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1
B0
Figure 34 3-Wire SPI Compatible Interface
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1.
B[15:9] are Control Address Bits
2.
B[8:0] are Control Data Bits
3.
ML/I2S is edge sensitive – the data is latched on the rising edge of ML/I2S.
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REGISTER MAP - 28 PIN SSOP
The complete register map is shown below. The detailed description can be found in the relevant text of the device description. The
WM8772EDS can be configured using the Control Interface. All unused bits should be set to ‘0’.
REGISTER
B15
B14
B13
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
R0(00h)
0
0
0
0
0
0
0
UPDATE
LDA1[7:0]
011111111
R1(01h)
0
0
0
0
0
0
1
UPDATE
RDA1[7:0]
011111111
R2(02h)
0
0
0
0
0
1
0
PL[8:5]
B2
B1
B0
PDWN
IZD
ATC
MUTE
DEEMP
100100000
All DAC
PHASE[8:6]
IWL[5:4]
BCP
DEFAULT
All DAC
FMT[1:0]
LRP
000000000
R3(03h)
0
0
0
0
0
1
1
R4(04h)
0
0
0
0
1
0
0
UPDATE
LDA2[7:0]
011111111
R5(05h)
0
0
0
0
1
0
1
UPDATE
RDA2[7:0]
011111111
R6(06h)
0
0
0
0
1
1
0
UPDATE
LDA3[7:0]
011111111
R7(07h)
0
0
0
0
1
1
1
UPDATE
RDA3[7:0]
011111111
R8(08h)
0
0
0
1
0
0
0
UPDATE
MASTDA[7:0]
011111111
R9(09h)
0
0
0
1
0
0
1
DEEMP[8:6]
R10(0Ah)
0
0
0
1
0
1
0
RATE[8:6]
R11(0Bh)
0
0
0
1
0
1
1
ADC
OSR
R12(0Ch)
0
0
0
1
1
0
0
0
R31(1Fh)
0
0
1
1
1
1
1
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DMUTE[5:3]
MS
010
0
MPD
DZFM[2:1]
PWRDNALL
DACPD[3:1]
0
0
0
RESET
00
ADCHP
AMUTE
ALL
ZCD
000000000
ADCPD
010000000
00
001000000
AMUTEL AMUTER
000000000
000000000
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CONTROL INTERFACE REGISTERS
ATTENUATOR CONTROL MODE
Setting the ATC register bit causes the left channel attenuation settings to be applied to both left and
right channel DACs from the next audio input sample. No update to the attenuation registers is
required for ATC to take effect.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC Channel Control
3
ATC
0
DESCRIPTION
Attenuator Control Mode:
0: Right channels use right
attenuations
1: Right channels use left
attenuations
INFINITE ZERO DETECT ENABLE
Setting the IZD register bit will enable the internal infinite zero detect function:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC Channel Control
4
IZD
0
DESCRIPTION
Infinite Zero Mute Enable
0 : Disable inifinite zero mute
1: Enable infinite zero mute
With IZD enabled, applying 1024 consecutive zero input samples each stereo channel will cause that
stereo channel outputs to be muted to VMID. Mute will be removed as soon as that stereo channel
receives a non-zero input.
DAC OUTPUT CONTROL
The DAC output control word determines how the left and right inputs to the audio Interface are
applied to the left and right DACs:
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC Control
8:5
PL[3:0]
1001
DESCRIPTION
PL[3:0]
Left
Output
Right
Output
0000
Mute
Mute
0001
Left
Mute
0010
Right
Mute
0011
(L+R)/2
Mute
0100
Mute
Left
0101
Left
Left
0110
Right
Left
0111
(L+R)/2
Left
1000
Mute
Right
1001
Left
Right
1010
Right
Right
1011
(L+R)/2
Right
1100
Mute
(L+R)/2
1101
Left
(L+R)/2
1110
Right
(L+R)/2
1111
(L+R)/2
(L+R)/2
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ADC AND DAC DIGITAL AUDIO INTERFACE CONTROL REGISTER
Interface format is selected via the FMT[1:0] register bits:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
Interface Control
1:0
FMT
[1:0]
00
DESCRIPTION
Interface Format Select:
00 : Right justified mode
01: Left justified mode
10: I2S mode
11: DSP mode A or B
2
In left justified, right justified or I S modes, the LRP register bit controls the polarity of LRC. If this bit
is set high, the expected polarity of LRC will be the opposite of that shown Figure 23, Figure 24 and
Figure 25. Note that if this feature is used as a means of swapping the left and right channels, a 1
sample phase difference will be introduced. In DSP modes, the LRP register bit is used to select
between mode A and mode B.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
Interface Control
2
LRP
0
DESCRIPTION
In left/right/I2S Modes:
LRC Polarity (normal)
0 : Normal LRC polarity
1: Inverted LRC polarity
In DSP Mode:
0 : DSP mode A
1: DSP mode B
By default, LRC and DIN1/2/3 are sampled on the rising edge of BCLK and should ideally change on
the falling edge. By default, LRC and DOUT are sampled on the rising edge of BCLK and should
ideally change on the falling edge. Data sources that change LRC and DOUT on the rising edge of
BCLK can be supported by setting the BCP register bit. Data sources that change LRC and DIN1/2/3
on the rising edge of BCLK can be supported by setting the BCP register bit. Setting BCP to 1
inverts the polarity of BCLK to the inverse of that shown in Figure 23 to Figure 33.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
Interface Control
3
BCP
0
DESCRIPTION
BCLK Polarity (DSP Modes):
0: Normal BCLK polarity
1: Inverted BCLK polarity
The IWL[1:0] bits are used to control the input word length.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
Interface Control
5:4
IWL
[1:0]
00
DESCRIPTION
Input Word Length:
00 : 16 bit data
01: 20 bit data
10: 24 bit data
11: 32 bit data
Note: 32-bit right justified mode is not supported.
In all modes, the data is signed 2's complement. The digital filters always input 24-bit data. If the
DAC is programmed to receive 16 or 20 bit data, the WM8772EDS pads the unused LSBs with
zeros. If the DAC is programmed into 32 bit mode, the 8 LSBs are ignored.
Note: In 24 bit I2S mode, any width of 24 bits or less is supported provided that LRC is high for a
minimum of 24 BCLKs and low for a minimum of 24 BCLKs.
A number of options are available to control how data from the Digital Audio Interface is applied to
the DAC channels.
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DAC OUTPUT PHASE
The DAC Phase control word determines whether the output of each DAC is non-inverted or inverted
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
DAC Phase
8:6
PHASE
[2:0]
000
DESCRIPTION
Bit
DAC
Phase
0
DAC1L/R
1 = invert
1
DAC2L/R
1 = invert
2
DAC3L/R
1 = invert
DIGITAL ZERO CROSS-DETECT
The Digital volume control also incorporates a zero cross detect circuit which detects a transition
through the zero point before updating the digital volume control with the new volume. This is
enabled by control bit DZCEN.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001001
DAC Control
0
ZCD
0
DESCRIPTION
DAC Digital Volume Zero Cross
Disable:
0: Zero cross detect enabled
1: Zero cross detect disabled
MUTE FLAG OUTPUT
The DZFM control bits allow the selection of the six DAC channel zero flag bits for output on the
MUTEB pin. A ‘1’ on MUTE indicates 1024 consecutive zero input samples to the DAC channels
selected.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001001
Zero Flag
2:1
DZFM[1:0]
00
DESCRIPTION
Selects the output MUTE pin (A ‘1’
indicates 1024 consecutive zero
input samples on the DAC channels
selected.
00: All channels zero
01: Channel 1 zero
10: Channel 2 zero
11: Channel 3 zero
DAC MUTE MODES
The WM8772EDS has individual mutes for each of the three DAC channels. Setting MUTE for a
channel will apply a ‘soft’ mute to the input of the digital filters of the channel muted.
REGISTER ADDRESS
0001001
DAC Mute
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BIT
5:3
LABEL
DMUTE
[2:0]
DEFAULT
000
DESCRIPTION
DAC Soft Mute Select
DMUTE [2:0]
DAC CHANNEL 1
DAC CHANNEL 2
DAC CHANNEL 3
000
Not MUTE
Not MUTE
Not MUTE
001
MUTE
Not MUTE
Not MUTE
010
Not MUTE
MUTE
Not MUTE
Not MUTE
011
MUTE
MUTE
100
Not MUTE
Not MUTE
MUTE
101
MUTE
Not MUTE
MUTE
110
Not MUTE
MUTE
MUTE
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Setting the MUTEALL register bit will apply a 'soft' mute to the input of all the DAC digital filters:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC Mute
0
MUTEALL
0
DESCRIPTION
Soft Mute Select:
0 : Normal operation
1: Soft mute all channels
Refer to Figure 19 for the plot of application and release of soft mute.
Note that all other means of muting the DAC channels: setting the PL[3:0] bits to 0, setting the
PDWN bit or setting attenuation to 0 will cause much more abrupt muting of the output.
ADC MUTE MODES
Each ADC channel also has a mute control bit, which mutes the inputs to the ADC.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001100
ADC Mute
0
AMUTER
0
ADC Mute Select:
0 : Normal operation
1: mute ADC right
DESCRIPTION
1
AMUTEL
0
ADC Mute Select:
0 : Normal operation
1: mute ADC left
2
AMUTEALL
0
ADC Mute Select:
0 : Normal operation
1: mute both ADC channels
DE-EMPHASIS MODE
Each stereo DAC channel has an individual de-emphasis control bit:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0001001
DAC De-Emphahsis
Control
[8:6]
DEEMPH
[1:0]
000
De-emphasis Channel Selection
Select:
DEEMPH
[1:0]
DAC CHANNEL 1
DAC CHANNEL 2
DAC CHANNEL 3
000
Not DE-EMPHASIS
Not DE-EMPHASIS
Not DE-EMPHASIS
001
DE-EMPHASIS
Not DE-EMPHASIS
Not DE-EMPHASIS
010
Not DE-EMPHASIS
DE-EMPHASIS
Not DE-EMPHASIS
011
DE-EMPHASIS
DE-EMPHASIS
Not DE-EMPHASIS
100
Not DE-EMPHASIS
Not DE-EMPHASIS
DE-EMPHASIS
101
DE-EMPHASIS
Not DE-EMPHASIS
DE-EMPHASIS
110
Not DE-EMPHASIS
DE-EMPHASIS
DE-EMPHASIS
Refer to Figure 7, Figure 8, Figure 9, Figure 10, Figure 11 and Figure 12 for details of the DeEmphasis performance at different sample rates.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC DEMP
1
DEEMP
ALL
0
DESCRIPTION
DEMMP Select:
0 : Normal operation
1: De-emphasis all channels
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POWERDOWN MODE AND ADC/DAC DISABLE
Setting the PDWN register bit immediately powers down the DAC’s on the WM8772EDS, overriding
the DACD powerdown bits control bits. All trace of the previous input samples are removed, but all
control register settings are preserved. When PDWN is cleared the digital filters will be reinitialised
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
Powerdown Control
2
PDWN
0
DESCRIPTION
Power Down all DAC’s Select:
0: All DAC’s enabled
1: All DAC’s disabled
The ADC and DACs may also be powered down individually by setting the ADCPD and DACPD
disable bits. Setting ADCD will disable the ADC and select a low power mode. The ADC digital filters
will be reset and will reinitialise when ADCPD is unset. Each Stereo DAC channel has a separate
disable DACPD[2:0]. Setting DACPD for a channel will disable the DACs and select a low power
mode.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001010
Powerdown Control
0
ADCPD
0
ADC Disable:
0: Active
1: Disable
DESCRIPTION
3:1
DACPD[2:0]
000
DAC Disable
DACPD [2:0]
DAC CHANNEL 1
DAC CHANNEL 2
DAC CHANNEL 3
000
Active
Active
Active
001
DISABLE
Active
Active
010
Active
DISABLE
Active
011
DISABLE
DISABLE
Active
100
Active
Active
DISABLE
101
DISABLE
Active
DISABLE
110
Active
DISABLE
DISABLE
111
DISABLE
DISABLE
DISABLE
MASTER POWERDOWN
This control bit powers down the references for the whole chop. Therefore for complete powerdown,
both the ADC and DACs should be powered down first before setting this bit.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001010
Interface Control
4
PWRDNALL
0
DESCRIPTION
Master Power Down Bit:
0: Not powered down
1: Powered down
MASTER MODE SELECT
Control bit MS selects between audio interface Master and Slave Modes. In Master mode LRC and
BCLK are outputs and are generated by the WM8772EDS. In Slave mode LRC and BCLK are inputs
to WM8772EDS.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0001010
Interface Control
5
MS
0
DAC Audio Interface Master/Slave
Mode Select:
0: Slave mode
1: Master mode
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MASTER MODE LRC FREQUENCY SELECT
In Master mode the WM8772EDS generates LRC and BCLK. These clocks are derived from the
master clock and the ratio of MCLK to LRC is set by RATE.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001010
Interface Control
8:6
RATE [2:0]
010
DESCRIPTION
Master Mode
MCLK:LRC Ratio Select:
000: 128fs (DAC only)
001: 192fs (DAC only)
010: 256fs
011: 384fs
100: 512fs
101: 768fs
ADC OVERSAMPLING RATE SELECT
For ADC operation at 96kHz it is recommended that the user set the ADCOSR bit. This changes the
ADC signal processing oversample rate to 64fs. The 64fs oversampling rate is only available in
modes were a 96KHz rate is supported, i.e. 256fs or 384fs. In all other modes the ADC will stay in a
128fs oversampling rate irrespective of what this bit is set to.
REGISTER ADDRESS
BIT
DEFAULT
DESCRIPTION
LABEL
0001011
ADC Oversampling Rate
8
ADCOSR
0
ADC Oversampling Rate Select:
0: 128x oversampling
1: 64x oversampling
ADC HIGHPASS FILTER DISABLE
The ADC digital filters contain a digital highpass filter. This defaults to enabled and can be disabled
using software control bit ADCHPD.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001100
ADC Control
3
ADCHPD
0
DESCRIPTION
ADC Highpass Filter Disable:
0: Highpass filter enabled
1: Highpass filter disabled
MUTE PIN DECODE
The MUTE pin can either be used an output or an input. When used as an input the MUTE pins
action can controlled by setting the DZFM bit to select the corresponding DAC for applying the MUTE
to. As an output its meaning is selected by the DZFM control bits. By default selecting the MUTE to
represent if DAC1 has received more than 1024 midrail samples will cause the MUTE to be asserted
a softmute on DAC1. Disabling the decode block will cause any logical high on the MUTE pin to
apply a softmute to all DAC’s.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001100
ADC Control
6
MPD
0
DESCRIPTION
MUTE Pin Decode Disable:
0: MUTE pin decode enable
1: MUTE pin decode disable
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DAC DIGITAL VOLUME CONTROL
The DAC volume may also be adjusted in the digital domain using independent digital attenuation
control registers
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0000000
Digital
Attenuation
DACL1
7:0
LDA1[7:0]
11111111
(0dB)
Digital Attenuation data for Left channel DACL1 in 0.5dB steps. See
Table 11
8
UPDATE
Not latched
0000001
Digital
Attenuation
DACR1
7:0
RDA1[6:0]
11111111
(0dB)
8
UPDATE
Not latched
0000100
Digital
Attenuation
DACL2
7:0
LDA2[7:0]
11111111
(0dB)
8
UPDATE
Not latched
0000101
Digital
Attenuation
DACR2
7:0
RDA2[7:0]
11111111
(0dB)
8
UPDATE
Not latched
0000110
Digital
Attenuation
DACL3
7:0
LDA3[7:0]
11111111
(0dB)
8
UPDATE
Not latched
0000111
Digital
Attenuation
DACR3
7:0
RDA3[7:0]
11111111
(0dB)
8
UPDATE
Not latched
0001000
Master
Digital
Attenuation
(all channels)
7:0
MASTDA
[7:0]
11111111
(0dB)
8
UPDATE
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store LDA1 in intermediate latch (no change to output)
1: Store LDA1 and update attenuation on all channels
Digital Attenuation data for Right channel DACR1 in 0.5dB steps.
See Table 11
Controls simultaneous update of all Attenuation Latches
0: Store RDA1 in intermediate latch (no change to output)
1: Store RDA1 and update attenuation on all channels.
Digital Attenuation data for Left channel DACL2 in 0.5dB steps. See
Table 11
Controls simultaneous update of all Attenuation Latches
0: Store LDA2 in intermediate latch (no change to output)
1: Store LDA2 and update attenuation on all channels.
Digital Attenuation data for Right channel DACR2 in 0.5dB steps.
See Table 11
Controls simultaneous update of all Attenuation Latches
0: Store RDA2 in intermediate latch (no change to output)
1: Store RDA2 and update attenuation on all channels.
Digital Attenuation data for Left channel DACL3 in 0.5dB steps. See
Table 11
Controls simultaneous update of all Attenuation Latches
0: Store LDA3 in intermediate latch (no change to output)
1: Store LDA3 and update attenuation on all channels.
Digital Attenuation data for Right channel DACR3 in 0.5dB steps.
See Table 11
Controls simultaneous update of all Attenuation Latches
0: Store RDA3 in intermediate latch (no change to output)
1: Store RDA3 and update attenuation on all channels.
Digital Attenuation data for all DAC channels in 0.5dB steps. See
Table 11
Controls simultaneous update of all Attenuation Latches
0: Store gain in intermediate latch (no change to output)
1: Store gain and update attenuation on all channels.
L/RDAX[7:0]
ATTENUATION LEVEL
00(hex)
-∞ dB (mute)
01(hex)
-127dB
:
:
:
:
:
:
FE(hex)
-0.5dB
FF(hex)
0dB
Table 11 Digital Volume Control Attenuation Levels
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SOFTWARE REGISTER RESET
Writing to register 11111 will cause a register reset, resetting all register bits to their default values.
The device will be held in this reset state until a subsequent register write to any address is
completed.
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APPLICATIONS INFORMATION
RECOMMENDED EXTERNAL COMPONENTS
RECOMMENDED EXTERNAL COMPONENTS VALUES
COMPONENT
REFERENCE
SUGGESTED
VALUE
DESCRIPTION
De-coupling for DVDD and AVDD.
C1 and C5
10µF
C2 to C4
0.1µF
C8 and C9
1µF
C6 and C10
0.1µF
C7 and C11
10µF
C12
10µF
Filtering for VREFP. Omit if AVDD low noise.
R1
33Ω
Filtering for VREP. Use 0Ω if AVDD low noise.
De-coupling for DVDD and AVDD.
Analogue input high pass filter capacitors
Reference de-coupling capacitors for VMID and ADCREF pin.
Table 12 External Components Description
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SUGGESTED ANALOGUE LOW PASS POST DAC FILTERS
It is recommended that a lowpass filter be applied to the output from each DAC channel for Hi Fi applications. Typically a
second order filter is suitable and provides sufficient attenuation of high frequency components (the unique low order, high
bit count multi-bit sigma delta DAC structure used in WM8772EDS produces much less high frequency output noise than
normal sigma delta DACs. This filter is typically also used to provide the 2x gain needed to provide the standard 2Vrms
output level from most consumer equipment.
Figure 35 shows a suitable post DAC filter circuit, with 2x gain. Alternative inverting filter architectures might also be used
with as good results.
1.0nF
10uF
1.8kΩ
Ω
7.5kΩ
Ω
51Ω
Ω
VOUT1L
10kΩ
Ω
680pF
4.7kΩ
Ω
4.7kΩ
Ω
OP_FIL
VOUT1R
OP_FIL
VOUT2L
OP_FIL
VOUT2R
OP_FIL
VOUT3L
OP_FIL
VOUT3R
OP_FIL
Figure 35 Recommended Post DAC Filter Circuit
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To ensure that system ‘pop’ noise is kept to a minimum when power is applied or removed, a
transistor clamp circuit arrangement may be added to the output connectors of the system. A
recommended clamp circuit configuration is shown below.
Figure 36 Output Clamp Circuit
When the +VS power supply is applied, PNP transistor Q10 of the trigger circuit is held on until
capacitor C49 is fully charged. With transistor Q10 held ‘on’, NPN transistors Q4 to Q9 of the clamp
circuits are also switched on holding the system outputs near to GND. When capacitor C49 is fully
charged transistors Q10 and Q4 to Q9 are switched off setting the outputs active.
When the +VS power supply is removed, PNP transistor Q11 of the trigger circuit is switched on. In
turn, transistors Q4 to Q9 of the clamp circuits are switched on holding the outputs of the evaluation
board near to GND until the rest of the circuitry on the board has settled.
Note: It is recommended that low Vcesat switching transistors should be used in this circuit to ensure
that the clamp is applied before the rest of the circuitry has time to power down.
Important: If a trigger circuit such as the one shown is to be used, it is important that the +VS
supply drops quicker than any other supply to ensure that the outputs are clamped during the
period when ‘pop’ noise may occur.
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PACKAGE DIMENSIONS
DS: 28 PIN SSOP (10.2 x 5.3 x 1.75 mm)
b
DM007.E
e
28
15
E1
1
D
E
GAUGE
PLANE
14
c
A A2
A1
Θ
L
0.25
L1
-C0.10 C
Symbols
A
A1
A2
b
c
D
e
E
E1
L
L1
θ
MIN
----0.05
1.65
0.22
0.09
9.90
7.40
5.00
0.55
o
0
REF:
Dimensions
(mm)
NOM
--------1.75
0.30
----10.20
0.65 BSC
7.80
5.30
0.75
1.25 REF
o
4
SEATING PLANE
MAX
2.0
0.25
1.85
0.38
0.25
10.50
8.20
5.60
0.95
o
8
JEDEC.95, MO-150
NOTES:
A. ALL LINEAR DIMENSIONS ARE IN MILLIMETERS.
B. THIS DRAWING IS SUBJECT TO CHANGE WITHOUT NOTICE.
C. BODY DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSION, NOT TO EXCEED 0.20MM.
D. MEETS JEDEC.95 MO-150, VARIATION = AH. REFER TO THIS SPECIFICATION FOR FURTHER DETAILS.
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WM8722EFT - 32 LEAD TQFP
MASTER CLOCK TIMING
t MCLKL
ADCMCLK/
DACMCLK
tMCLKH
t MCLKY
Figure 37 ADC and DAC Master Clock Timing Requirements
Test Conditions
AVDD, VREFP = 5V, DVDD = 3.3V, AGND, VREFN = 0V, AGND, DGND = 0V, TA = +25oC, fs = 48kHz, DACMCLK and
ADCMCLK = 256fs unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
System Clock Timing Information
ADCMCLK and DACMCLK
System clock pulse width high
tMCLKH
11
ns
ADCMCLK and DACMCLK
System clock pulse width low
tMCLKL
11
ns
ADCMCLK and DACMCLK
System clock cycle time
tMCLKY
28
ns
ADCMCLK and DACMCLK Duty
cycle
40:60
60:40
Table 13 Master Clock Timing Requirements
DIGITAL AUDIO INTERFACE – MASTER MODE
ADCBCLK
ADCLRC
DACBCLK
WM8772
CODEC DACLRC
DSP/
ENCODER/
DECODER
DOUT
DIN1/2/3
3
Figure 38 Audio Interface - Master Mode
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ADCBCLK/
DACBCLK
(Outputs)
tDL
ADCLRC/
DACLRC
(Outputs)
tDDA
DOUT
DIN1/2/3
tDST
tDHT
Figure 39 Digital Audio Data Timing – Master Mode
Test Conditions
AVDD, VREFP = 5V, DVDD = 3.3V, AGND, VREFN, DGND = 0V, TA = +25oC, Master Mode, fs = 48kHz, DACMCLK and
ADCMCLK = 256fs unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Audio Data Input Timing Information
ADCLRC/DACLRC
propagation delay from
ADCBCLK/DACBCLK
falling edge
tDL
0
10
ns
DOUT propagation delay
from ADCBCLK falling edge
tDDA
0
10
ns
DIN1/2/3 setup time to
DACBCLK rising edge
tDST
10
ns
DIN1/2/3 hold time from
DACBCLK rising edge
tDHT
10
ns
Table 14 Digital Audio Data Timing – Master Mode
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DIGITAL AUDIO INTERFACE – SLAVE MODE
ADCBCLK
ADCLRC
DSP
ENCODER/
DECODER
WM8772 DACBCLK
CODEC
DACLRC
DOUT
DIN1/2/3
3
Figure 40 Audio Interface – Slave Mode
tBCH
DACBCLK/
ADCBCLK
tBCL
tBCY
DACLRC/
ADCLRC
tDS
tLRH
tLRSU
DIN1/2/3
tDD
tDH
DOUT
Figure 41 Digital Audio Data Timing – Slave Mode
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Test Conditions
AVDD = 5V, DVDD = 3.3V, AGND = 0V, DGND = 0V, TA = +25oC, Slave Mode, fs = 48kHz, DACMCLK and ADCMCLK = 256fs
unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Audio Data Input Timing Information
ADCBCLK/DACBCLK cycle
time
tBCY
50
ns
ADCBCLK/DACBCLK pulse
width high
tBCH
20
ns
ADCBCLK/DACBCLK pulse
width low
tBCL
20
ns
ADCLRC/DACLRC set-up
time to
ADCBCLK/DACBCLK rising
edge
tLRSU
10
ns
ADCLRC/DACLRC hold
time from
ADCBCLK/DACBCLK rising
edge
tLRH
10
ns
DIN1/2/3 set-up time to
DACBCLK rising edge
tDS
10
ns
DIN1/2/3 hold time from
DACBCLK rising edge
tDH
10
ns
DOUT propagation delay
from ADCBCLK falling edge
tDD
0
10
ns
Table 15 Digital Audio Data Timing – Slave Mode
MPU INTERFACE TIMING
tCSL
tCSH
ML/I2S
tSCY
tSCH
tCSS
tSCL
tSCS
MC/IWL
MD/DM
LSB
tDSU
tDHO
Figure 42 SPI Compatible Control Interface Input Timing
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Test Conditions
AVDD = 5V, DVDD = 3.3V, AGND, DGND = 0V, TA = +25oC, fs = 48kHz, DACMCLK and ADCMCLK = 256fs unless otherwise
stated
SYMBOL
MIN
MC/IWL rising edge to ML/I2S rising edge
PARAMETER
tSCS
60
TYP
MAX
UNIT
ns
MC/IWL pulse cycle time
tSCY
80
ns
MC/IWL pulse width low
tSCL
30
ns
MC/IWL pulse width high
tSCH
30
ns
MD/DM to MC/IWL set-up time
tDSU
20
ns
MC/IWL to MD/DM hold time
tDHO
20
ns
ML/I2S pulse width low
tCSL
20
ns
ML/I2S pulse width high
tCSH
20
ns
ML/I2S rising to MC/IWL rising
tCSS
20
ns
Table 16 3-Wire SPI Compatible Control Interface Input Timing Information
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DEVICE DESCRIPTION
INTRODUCTION
WM8772EFT is a complete 6-channel DAC, 2-channel ADC audio codec, including digital
interpolation and decimation filters, multi-bit sigma delta stereo ADC, and switched capacitor multibit sigma delta DACs with digital volume controls on each channel and output smoothing filters.
The device is implemented as three separate stereo DACs and a stereo ADC in a single package
and controlled by a single interface.
Each stereo DAC has its own data input DIN1/2/3. DAC word clock DACLRC, DAC bit clock
DACBCLK and DAC master clock DACMCLK are shared between them. The stereo ADC has it’s
own data output DOUT, word clock ADCLRC, bit clock ADCBCLK and ADC master clock ADCMCLK.
This allows the ADC and DAC to run independently.
The Audio Interface may be configured to operate in either master or slave mode. In Slave mode
ADCLRC and ADCBCLK, DACLRC and DACBCLK are all inputs. In Master mode ADCLRC and
ADCBCLK, DACLRC and DACBCLK are all outputs. The DAC’s and ADC can be in any combination
of master or slave mode.
Each DAC has its own digital volume control that is adjustable in 0.5dB steps. The digital volume
controls may be operated independently. In addition, a zero cross detect circuit is provided for each
DAC for the digital volume controls. The digital volume control detects a transition through the zero
point before updating the volume. This minimises audible clicks and ‘zipper’ noise as the gain values
change.
Control of internal functionality of the device is by 3-wire serial or pin programmable control interface.
The software control interface may be asynchronous to the audio data interface as control data will
be re-synchronised to the audio processing internally.
Operation using master clocks of 128fs, 192fs, 256fs, 384fs, 512fs or 768fs is provided for the DAC,
and 256fs, 384fs, 512fs, and 768fs is provided for the ADC. In Slave mode selection between clock
rates is automatically controlled. In master mode, the sample rate is set by control bits ADCRATE
and DACRATE. Audio sample rates (fs) from less than 8ks/s up to 192ks/s are allowed for the DAC
and from less than 32ks/s up to 96ks/s for the ADC, provided the appropriate master clock is input.
The audio data interface supports right, left and I2S interface formats along with a highly flexible DSP
serial port interface.
AUDIO DATA SAMPLING RATES
In a typical digital audio system there is only one central clock source producing a reference clock to
which all audio data processing is synchronised. This clock is often referred to as the audio system’s
Master Clock. The external master system clock can be applied directly through the ADC and DAC
MCLK input pin(s) with no software configuration necessary. In a system where there are a number
of possible sources for the reference clock it is recommended that the clock source with the lowest
jitter be used to optimise the performance of the ADC and DAC.
The DAC master clock for WM8772EFT supports audio sampling rates from 128fs to 768fs, where fs
is the audio sampling frequency (DACLRC) typically 32kHz, 44.1kHz, 48kHz, 96kHz or 192kHz (for
DAC operation only). The ADC master clock for WM8772EFT supports audio sampling rates from
256fs to 768fs, where fs is the audio sampling frequency (ADCLRC) typically 32kHz, 44.1kHz,
48kHz, 96kHz or 192kHz. The master clock is used to operate the digital filters and the noise shaping
circuits.
In Slave mode the WM8772EFT has a master clock detection circuit that automatically determines
the relationship between the system clock frequency and the sampling rate (to within +/- 32 master
clocks). If there is a greater than 32 clocks error the interface defaults to 768fs mode. The master
clocks must be synchronised with ADCLRC and DACLRC respectively, although the WM8772EFT is
tolerant of phase variations or jitter on this clock. Table 6 shows the typical master clock frequency
inputs for the WM8772EFT.
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The signal processing for the WM8772EFT typically operates at an oversampling rate of 128fs for
both ADC and DAC. The exception to this for the DAC is for operation with a 128/192fs system clock,
e.g. for 192kHz operation, when the oversampling rate is 64fs. For ADC operation at 96kHz it is
recommended that the user set the ADCOSR bit. This changes the ADC signal processing
oversample rate to 64fs.
SAMPLING
RATE
(DACLRC/
ADCLRC)
System Clock Frequency (MHz)
128fs
192fs
256fs
384fs
512fs
768fs
32kHz
4.096
6.144
8.192
12.288
16.384
24.576
44.1kHz
5.6448
8.467
11.2896
16.9340
22.5792
33.8688
24.576
36.864
48kHz
6.144
9.216
12.288
18.432
96kHz
12.288
18.432
24.576
36.864
192kHz
24.576
36.864
Unavailable Unavailable
Unavailable Unavailable Unavailable Unavailable
Table 17 System Clock Frequencies Versus Sampling Rate
(ADC does not support 128fs and 192fs)
HARDWARE CONTROL MODES
When the MODE pin is held high, the following hardware modes of operation are available.
Note: When in hardware mode the ADC and DAC will only run in slave mode.
MUTE AND AUTOMUTE OPERATION
In both hardware and software modes, MUTE controls the selection of MUTE directly, and can be
used to enable and disable the automute function. This pin becomes an output when left floating and
indicates infinite ZERO detect (IZD) has been detected.
DESCRIPTION
0
Normal Operation
1
Mute DAC channels
Floating
Enable IZD, MUTE becomes an output to indicate when IZD occurs.
L=IZD detected, H=IZD not detected.
Table 18 Mute and Automute Control
Figure 43 shows the application and release of MUTE whilst a full amplitude sinusoid is being played
at 48kHz sampling rate. When MUTE (lower trace) is asserted, the output (upper trace) begins to
decay exponentially from the DC level of the last input sample. The output will decay towards VMID
with a time constant of approximately 64 input samples. If MUTE is applied to all channels for 1024
or more input samples the outputs will be connected directly to VMID if IZD is set. When MUTE is deasserted, the output will restart immediately from the current input sample.
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1.5
1
0.5
0
-0.5
-1
-1.5
-2
-2.5
0
0.001
0.002
0.003
0.004
0.005
0.006
Time(s)
Figure 43 Application and Release of Soft Mute
The MUTE pin is an input to select mute or not mute. MUTE is active high; taking the pin high causes
the filters to soft mute, ramping down the audio signal over a few milliseconds. Taking MUTE low
again allows data into the filter.
The automute function detects a series of ZERO value audio samples of 1024 samples long being
applied to both channels. After such an event, a latch is set whose output (AUTOMUTED) is wire
OR’ed through a 10kΩ resistor to the MUTE pin. Thus if the MUTE pin is not being driven, the
automute function will assert mute.
If MUTE is tied low, AUTOMUTED is overridden and will not mute unless the IZD register bit is set. If
MUTE is driven from a bi-directional source, then both MUTE and automute functions are available. If
MUTE is not driven, AUTOMUTED appears as a weak output (10kΩ source impedance) and can be
used to drive external mute circuits. AUTOMUTED will be removed as soon as any channel receives
a non-ZERO input.
A diagram showing how the various Mute modes interact is shown below Figure 20.
IZD (Register Bit)
AUTOMUTED
(Internal Signal)
10kΩ
Ω
MUTE
PIN
SOFTMUTE
(Internal
Signal)
MUTE (Register Bit)
Figure 44 Selection Logic for MUTE Modes
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INPUT FORMAT SELECTION
In hardware mode, ML/I2S and MC/IWL become input controls for selection of input data format type
and input data word length for both the ADC and DAC.
ML/I2S
MC/IWL
0
0
24-bit right justified
INPUT DATA MODE
0
1
20-bit right justified
1
0
16-bit I2S
1
1
24-bit I2S
Table 19 Input Format Selection
Note:
In 24 bit I2S mode, any width of 24 bits or less is supported provided that the left/right clocks
(ADCLRC and DACLRC) are high for a minimum of 24 bit clocks (ADCBCLK and DACBCLK) and
low for a minimum of 24 bit clocks.
DE-EMPHASIS CONTROL
In hardware mode, the MD/DM pin becomes an input control for selection of de-emphasis filtering to
be applied.
MD/DM
DE-EMPHASIS
0
Off
1
On
Table 20 De-emphasis Control
DIGITAL AUDIO INTERFACE
MASTER AND SLAVE MODES
The audio interface operates in either Slave or Master mode, selectable using the DACMS and
ADCMS control bits. In both Master and Slave modes DIN1/2/3 are always inputs to the
WM8772EFT and DOUT is always an output. The default is Slave mode for ADC and DAC.
In Slave mode, ADCLRC, DACLRC and ADCBCLK, DACBCLK are inputs to the WM8772EFT
(Figure 21). DIN1/2/3, ADCLRC and DACLRC are sampled by the WM8772EFT on the rising edge of
ADCBCLK and DACBCLK respectively. ADC data is output on DOUT and changes on the falling
edge of ADCBCLK.
By setting the control bit DACBCP the polarity of DACBCLK may be reversed so that DIN1/2/3 and
DACLRC are sampled on the falling edge of DACBCLK.
By setting the control bit ADCBCP the polarity of ADCBCLK may be reversed so that ADCLRC is
sampled on the falling edge of ADCBCLK and DOUT changes on the rising edge of ADCBCLK.
ADCBCLK
ADCLRC
DSP
ENCODER/
DECODER
WM8772 DACBCLK
CODEC
DACLRC
DOUT
DIN1/2/3
3
Figure 45 Slave Mode
In Master mode, ADCLRC, DACLRC, ADCBCLK and DACBCLK are outputs from the WM8772EFT
(Figure 22). ADCLRC, DACLRC, ADCBCLK and DACBCLK are generated by the WM8772EFT.
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DIN1/2/3 are sampled by the WM8772EFT on the rising edge of DACBCLK so the controller must
output DAC data that changes on the falling edge of DACBCLK. ADC data is output on DOUT and
changes on the falling edge of ADCBCLK.
By setting control bit DACBCP the polarity of DACBCLK may be reversed so that DIN1/2/3 are
sampled on the falling edge of DACBCLK.
By setting control bit ADCBCP the polarity of ADCBCLK may be reversed so that DOUT changes on
the rising edge of ADCBCLK.
ADCBCLK
ADCLRC
DACBCLK
DSP/
ENCODER/
DECODER
WM8772
CODEC DACLRC
DOUT
DIN1/2/3
3
Figure 46 Master Mode
AUDIO INTERFACE FORMATS
Audio data is applied to the internal DAC filters, or output from the ADC filters, via the Digital Audio
Interface. 5 popular interface formats are supported:
•
Left Justified mode
•
Right Justified mode
•
I2S mode
•
DSP mode A
•
DSP mode B
All 5 formats send the MSB first and support word lengths of 16, 20, 24 and 32 bits, with the
exception of 32 bit right justified mode, which is not supported.
In left justified, right justified and I2S modes, the digital audio interface receives DAC data on the
DIN1/2/3 inputs and outputs ADC data on DOUT. Audio Data for each stereo channel is time
multiplexed with ADCLRC or DACLRC indicating whether the left or right channel is present.
ADCLRC or DACLRC is also used as a timing reference to indicate the beginning or end of the data
words.
In left justified, right justified and I2S modes, the minimum number of DACBCLK/ADCBCLK’s per
DACLRC/ADCLRC period is 2 times the selected word length. ADCLRC/DACLRC must be high for a
minimum of word length DACBCLK/ADCBCLK’s and low for a minimum of word length
DACBCLK/ADCBCLK’s. Any mark to space ratio on ADCLRC/DACLRC is acceptable provided the
above requirements are met.
In DSP mode A or mode B, all 6 DAC channels are time multiplexed onto DIN1. DACLRC is used as
a frame sync signal to identify the MSB of the first word. The minimum number of DACBCLK’s per
DACLRC period is 6 times the selected word length. Any mark to space ratio is acceptable on
DACLRC provided the rising edge is correctly positioned. The ADC data may also be output in DSP
mode A or mode B, with ADCLRC used as a frame sync to identify the MSB of the first word. The
minimum number of ADCBCLK’s per ADCLRC period is 2 times the selected word length
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LEFT JUSTIFIED MODE
In left justified mode, the MSB of DIN1/2/3 is sampled by the WM8772EFT on the first rising edge of
DACBCLK following a DACLRC transition. The MSB of the ADC data is output on DOUT and
changes on the same falling edge of ADCBCLK as ADCLRC and may be sampled on the rising edge
of ADCBCLK. ADCLRC and DACLRC are high during the left samples and low during the right
samples (Figure 47).
1/fs
LEFT CHANNEL
RIGHT CHANNEL
DACLRC/
ADCLRC
DACBCLK/
ADCBCLK
DIN1/2/3/
DOUT
1
2
3
n-2 n-1
MSB
n
1
LSB
2
3
n-2 n-1
MSB
n
LSB
Figure 47 Left Justified Mode Timing Diagram
RIGHT JUSTIFIED MODE
In right justified mode, the LSB of DIN1/2/3 is sampled by the WM8772EFT on the
rising edge of DACBCLK preceding a DACLRC transition. The LSB of the ADC data is
output on DOUT and changes on the falling edge of ADCBCLK preceding a ADCLRC
transition and may be sampled on the rising edge of ADCBCLK. ADCLRC and DACLRC
are high during the left samples and low during the right samples (
Figure 48).
1/fs
LEFT CHANNEL
RIGHT CHANNEL
DACLRC/
ADCLRC
DACBCLK/
ADCBCLK
DIN1/2/3/
DOUT
1
2
3
n-2 n-1
MSB
n
LSB
1
MSB
2
3
n-2 n-1
n
LSB
Figure 48 Right Justified Mode Timing Diagram
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2
I S MODE
In I2S mode, the MSB of DIN1/2/3 is sampled by the WM8772EFT on the second rising edge of
BCLK following a DACLRC transition. The MSB of the ADC data is output on DOUT and changes on
the first falling edge of BCLK following an ADCLRC transition and may be sampled on the rising edge
of BCLK. ADCLRC and DACLRC are low during the left samples and high during the right samples.
1/fs
LEFT CHANNEL
RIGHT CHANNEL
DACLRC/
ADCLRC
DACBCLK/
ADCBCLK
1 BCLK
1 BCLK
DIN1/2/3/
DOUT
1
2
3
n-2 n-1
n
1
LSB
MSB
2
3
n-2 n-1
n
LSB
MSB
Figure 49 I2S Mode Timing Diagram
DSP MODE A
In DSP mode A, the MSB of DAC channel 1 left data is sampled by the WM8772EFT on the second
rising edge on DACBCLK following a DACLRC rising edge. DAC channel 1 right and DAC channels 2
and 3 data follow DAC channel 1 left data (Figure 50).
Figure 50 DSP Mode Audio Interface - Mode A Slave, DAC
1 BCLK
1 BCLK
1/fs
DACLRC
DACBCLK
CHANNEL 1
LEFT
DIN1
1
2
MSB
CHANNEL 1
RIGHT
n-1 n
1
2
n-1 n
CHANNEL 2
LEFT
1
2
CHANNEL 3
RIGHT
NO VALID DATA
n-1 n
LSB
Input Word Length (IWL)
Figure 51 DSP Mode Audio Interface - Mode A Master, DAC
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The MSB of the left channel ADC data is output on DOUT and changes on the first falling edge of
ADCBCLK following a low to high ADCLRC transition and may be sampled on the rising edge of
ADCBCLK. The right channel ADC data is contiguous with the left channel data (Figure 52)
Figure 52 DSP Mode Audio Interface - Mode A Slave, ADC
1 BCLK
1 BCLK
1/fs
ADCLRC
ADCBCLK
LEFT CHANNEL
DOUT
1
2
MSB
RIGHT CHANNEL
n
n-1
1
2
n-1
NO VALID DATA
n
LSB
Input Word Length (IWL)
Figure 53 DSP Mode Audio Interface - Mode A Master, ADC
DSP MODE B
In DSP mode B, the MSB of DAC channel 1 left data is sampled by the WM8772EFT on the first
DACBCLK rising edge following a DACLRC rising edge. DAC channel 1 right and DAC channels 2
and 3 data follow DAC channel 1 left data (Figure 54).
Figure 54 DSP Mode Audio Interface - Mode B Slave, DAC
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1/fs
DACLRC
DACBCLK
CHANNEL 1
LEFT
DIN1
1
2
CHANNEL 1
RIGHT
n
n-1
MSB
1
2
n-1
CHANNEL 2
LEFT
n
1
2
CHANNEL 3
RIGHT
n-1
n
NO VALID DATA
1
LSB
Input Word Length (IWL)
Figure 55 DSP Mode Audio Interface - Mode B Master, DAC
The MSB of the left channel ADC data is output on DOUT and changes on the same falling edge of
ADCBCLK as the low to high ADCLRC transition and may be sampled on the rising edge of
ADCBCLK. The right channel ADC data is contiguous with the left channel data (Figure 56).
Figure 56 DSP Mode Audio Interface - Mode A Slave, ADC
1/fs
ADCLRC
BCK
LEFT CHANNEL
DOUT
1
2
MSB
RIGHT CHANNEL
n
n-1
1
2
n-1
NO VALID DATA
n
1
LSB
Input Word Length (IWL)
Figure 57 DSP Mode Audio Interface - Mode B Master, ADC
In both DSP mode A and mode B , DACL1 is always sent first, followed immediately by DACR1 and
the data words for the other 6 channels. No BCLK edges are allowed between the data words. The
word order is DAC1 left, DAC1 right, DAC2 left, DAC2 right, DAC3 left, DAC3 right.
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POWERDOWN MODES
The WM8772EFT has powerdown control bits allowing specific parts of the WM8772EFT to be
powered off when not being used. Control bit ADCPD powers off the ADC. The three stereo DACs
each have a separate powerdown control bit, DACPD[2:0] allowing individual stereo DACs to be
powered off when not in use. Setting ADCPD and DACPD[2:0] will powerdown everything except the
references VMID and REFADC. These may be powered down by setting PDWN. Setting PDWN will
override all other powerdown control bits. It is recommended that the ADC and DACs are powered
down before setting PDWN.
ZERO DETECT
The WM8772EFT has a zero detect circuit for each DAC channel that detects when 1024
consecutive zero samples have been input. The MUTE pin output may be programmed to output the
zero detect signal (see Table 10) which may then be used to control external muting circuits. A ‘1’ on
MUTE indicates a zero detect. The zero detect may also be used to automatically enable DAC mute
by setting IZD.
DZFM[1:0]
MUTE
00
All channels zero
01
Channel 1 zero
10
Channel 2 zero
11
Channel 3 zero
Table 21 Zero Flag Output Select
SOFTWARE CONTROL INTERFACE OPERATION
The WM8772EFT is controlled using a 3-wire serial interface in software mode or pin programmable
in hardware mode.
The control mode is selected by the state of the MODE pin.
The control interfaces are 5V tolerant; meaning that the control interface input signals ML/I2S,
MC/IWL and MD/DM may have an input high level of 5V while DVDD is 3V. Input thresholds are
determined by DVDD. MUTE and MODE are also 5V tolerant.
3-WIRE (SPI COMPATIBLE) SERIAL CONTROL MODE
MD/DM is used for the program data, MC/IWL is used to clock in the program data and ML/I2S is
used to latch the program data. MD/DM is sampled on the rising edge of MC/IWL. The 3-wire
interface protocol is shown in Figure 34.
ML/I2S
MC/IWL
MD/DM
B15
B14
B13
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1
B0
Figure 58 3-Wire SPI Compatible Interface
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4.
B[15:9] are Control Address Bits
5.
B[8:0] are Control Data Bits
6.
ML/I2S is edge-sensitive – the data is latched on the rising edge of ML/I2S.
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REGISTER MAP – 32 PIN TQFP
The complete register map is shown below. The detailed description can be found in the relevant text of the device description. The
WM8772EFT can be configured using the Control Interface. All unused bits should be set to ‘0’.
REGISTER
B15
B14
B13
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
R0(00h)
0
0
0
0
0
0
0
UPDATE
LDA1[7:0]
011111111
R1(01h)
0
0
0
0
0
0
1
UPDATE
RDA1[7:0]
011111111
R2(02h)
0
0
0
0
0
1
0
PL[8:5]
B2
B1
PDWN
IZD
ATC
DACIWL[5:4]
DACBCP
DACLRP
DEFAULT
MUTE
DEEMP
All DAC
PHASE[8:6]
B0
100100000
All DAC
DACFMT[1:0]
000000000
R3(03h)
0
0
0
0
0
1
1
R4(04h)
0
0
0
0
1
0
0
UPDATE
LDA2[7:0]
011111111
R5(05h)
0
0
0
0
1
0
1
UPDATE
RDA2[7:0]
011111111
R6(06h)
0
0
0
0
1
1
0
UPDATE
LDA3[7:0]
011111111
R7(07h)
0
0
0
0
1
1
1
UPDATE
RDA3[7:0]
011111111
R8(08h)
0
0
0
1
0
0
0
UPDATE
MASTDA[7:0]
011111111
R9(09h)
0
0
0
1
0
0
1
DEEMP[8:6]
R10(0Ah)
0
0
0
1
0
1
0
DACRATE[8:6]
R11(0Bh)
0
0
0
1
0
1
1
ADC
OSR
R12(0Ch)
0
0
0
1
1
0
0
0
R31(1Fh)
0
0
1
1
1
1
1
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SYNC
DMUTE[5:3]
DACMS
PWRDN
DACPD[3:1]
ALL
ADCRATE[7:5]
ADCMS
MPD
ADCLRP
ADCBCP
DZFM[2:1]
RESET
ADCIWL[3:2]
ADCHP
AMUTE
ALL
ZCD
000000000
ADCPD
010000000
ADCFMT[1:0]
001000000
AMUTEL AMUTER
000000000
000000000
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CONTROL INTERFACE REGISTERS
ATTENUATOR CONTROL MODE
Setting the ATC register bit causes the left channel attenuation settings to be applied to both left and
right channel DACs from the next audio input sample. No update to the attenuation registers is
required for ATC to take effect.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC Channel Control
3
ATC
0
DESCRIPTION
Attenuator Control Mode:
0: Right channels use right
attenuations
1: Right channels use left
attenuations
INFINITE ZERO DETECT ENABLE
Setting the IZD register bit will enable the internal infinite zero detect function:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC Channel Control
4
IZD
0
DESCRIPTION
Infinite zero mute enable
0: Disable infinite zero mute
1: Enable infinite zero mute
With IZD enabled, applying 1024 consecutive zero input samples to each input will cause the
relevant DAC to be muted to VMID. Mute will be removed as soon as that channel receives a non-zero
input.
DAC OUTPUT CONTROL
The DAC output control word determines how the left and right inputs to the audio Interface are
applied to the left and right DACs:
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC Control
8:5
PL[3:0]
1001
DESCRIPTION
PL[3:0]
Left
Output
Right
Output
0000
Mute
Mute
0001
Left
Mute
0010
Right
Mute
0011
(L+R)/2
Mute
0100
Mute
Left
0101
Left
Left
0110
Right
Left
0111
(L+R)/2
Left
1000
Mute
Right
1001
Left
Right
1010
Right
Right
1011
(L+R)/2
Right
1100
Mute
(L+R)/2
1101
Left
(L+R)/2
1110
Right
(L+R)/2
1111
(L+R)/2
(L+R)/2
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DAC DIGITAL AUDIO INTERFACE CONTROL REGISTER
Interface format is selected via the DACFMT[1:0] register bits:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
Interface Control
1:0
DACFMT
[1:0]
00
DESCRIPTION
Interface Format Select:
00 : Right justified mode
01: Left justified mode
10: I2S mode
11: DSP mode A or B
2
In left justified, right justified or I S modes, the DACLRP register bit controls the polarity of DACLRC.
If this bit is set high, the expected polarity of DACLRC will be the opposite of that shown Figure 23,
Figure 24 and Figure 25. Note that if this feature is used as a means of swapping the left and right
channels, a 1 sample phase difference will be introduced. In DSP modes, the DACLRP register bit is
used to select between mode A and mode B.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
Interface Control
2
DACLRP
0
DESCRIPTION
In Left/Right/I2S Modes:
DACLRC Polarity (normal)
0 : Normal DACLRC polarity
1: Inverted DACLRC polarity
In DSP Mode:
0 : DSP mode A
1: DSP mode B
By default, DACLRC and DIN1/2/3 are sampled on the rising edge of DACBCLK and should ideally
change on the falling edge. Data sources that change DACLRC and DIN1/2/3 on the rising edge of
DACBCLK can be supported by setting the BCP register bit. Setting DACBCP to 1 inverts the
polarity of DACBCLK to the inverse of that shown in Figure 47 to Figure 57.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0000011
Interface Control
3
DACBCP
0
DACBCLK Polarity (DSP Modes)
0 : Normal BCLK polarity
1: Inverted BCLK polarity
The DACIWL[1:0] bits are used to control the input word length.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
Interface Control
5:4
DACIWL
[1:0]
00
DESCRIPTION
Input Word Length:
00 : 16 bit data
01: 20 bit data
10: 24 bit data
11: 32 bit data
Note: If 32-bit mode is selected in right justified mode, the WM8772EFT defaults to 24 bits.
In all modes, the data is signed 2's complement. The digital filters always input 24-bit data. If the
DAC is programmed to receive 16 or 20 bit data, the WM8772EFT pads the unused LSBs with zeros.
If the DAC is programmed into 32 bit mode, the 8 LSBs are ignored.
Note: In 24 bit I2S mode, any width of 24 bits or less is supported provided that DACLRC is high for a
minimum of 24 BCLKs and low for a minimum of 24 BCLKs.
A number of options are available to control how data from the Digital Audio Interface is applied to
the DAC channels.
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DAC OUTPUT PHASE
The DAC Phase control word determines whether the output of each DAC is non-inverted or inverted
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000011
DAC Phase
8:6
PHASE
[2:0]
000
DESCRIPTION
Bit
DAC
Phase
0
DAC1L/R
1 = invert
1
DAC2L/R
1 = invert
2
DAC3L/R
1 = invert
DIGITAL ZERO CROSS-DETECT
The Digital volume control also incorporates a zero cross detect circuit which detects a transition
through the zero point before updating the digital volume control with the new volume. This is
enabled by control bit DZCEN.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001001
DAC Control
0
ZCD
0
DESCRIPTION
DAC Digital Volume Zero Cross
Disable:
0: Zero cross detect enabled
1: Zero cross detect disabled
MUTE FLAG OUTPUT
The DZFM control bits allow the selection of the six DAC channel zero flag bits for output on the
MUTEB pin. A ‘1’ on MUTE indicates 1024 consecutive zero input samples to the DAC channels
selected.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0001001
Zero Flag
2:1
DZFM[1:0]
00
Selects the output MUTE pin (A ‘1’
indicates 1024 consecutive zero
input samples on the DAC
channels selected.
00: All channels zero
01: Channel 1 zero
10: Channel 2 zero
11: Channel 3 zero
DAC MUTE MODES
The WM8772EFT has individual mutes for each of the three DAC channels. Setting MUTE for a
channel will apply a ‘soft’ mute to the input of the digital filters of the channel muted.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001001
DAC Mute
5:3
DMUTE
[2:0]
000
DESCRIPTION
DAC Soft Mute Select
DMUTE [2:0]
DAC CHANNEL 1
DAC CHANNEL 2
DAC CHANNEL 3
000
Not MUTE
Not MUTE
Not MUTE
001
MUTE
Not MUTE
Not MUTE
010
Not MUTE
MUTE
Not MUTE
Not MUTE
011
MUTE
MUTE
100
Not MUTE
Not MUTE
MUTE
101
MUTE
Not MUTE
MUTE
110
Not MUTE
MUTE
MUTE
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Setting the MUTEALL register bit will apply a 'soft' mute to the input of all the DAC digital filters:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC Mute
0
MUTEALL
0
DESCRIPTION
Soft Mute Select:
0 : Normal operation
1: Soft mute all channels
Refer to Figure 43 for the plot of application and release of soft mute.
Note that all other means of muting the DAC channels: setting the PL[3:0] bits to 0, setting the
PDWN bit or setting attenuation to 0 will cause much more abrupt muting of the output.
ADC MUTE MODES
Each ADC channel also has a mute control bit, which mutes the inputs to the ADC.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001100
ADC Mute
0
AMUTER
0
ADC Mute Select:
0 : Normal operation
1: mute ADC right
DESCRIPTION
1
AMUTEL
0
ADC Mute Select:
0 : Normal operation
1: mute ADC left
2
AMUTEALL
0
ADC Mute Select:
0 : Normal operation
1: mute both ADC channels
DE-EMPHASIS MODE
Each stereo DAC channel has an individual de-emphasis control bit:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0001001
DAC De-emphahsis
Control
[8:6]
DEEMPH
000
De-emphasis Channel Selection
Select:
[1:0]
DEEMPH
[1:0]
DAC CHANNEL 1
DAC CHANNEL 2
DAC CHANNEL 3
000
Not DE-EMPHASIS
Not DE-EMPHASIS
Not DE-EMPHASIS
001
DE-EMPHASIS
Not DE-EMPHASIS
Not DE-EMPHASIS
010
Not DE-EMPHASIS
DE-EMPHASIS
Not DE-EMPHASIS
011
DE-EMPHASIS
DE-EMPHASIS
Not DE-EMPHASIS
100
Not DE-EMPHASIS
Not DE-EMPHASIS
DE-EMPHASIS
101
DE-EMPHASIS
Not DE-EMPHASIS
DE-EMPHASIS
110
Not DE-EMPHASIS
DE-EMPHASIS
DE-EMPHASIS
Refer to Figure 7, Figure 8, Figure 9, Figure 10, Figure 11 and Figure 12 for details of the DeEmphasis performance at different sample rates.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
DAC DEMP
1
DEEMP
ALL
0
DESCRIPTION
DEMMP Select:
0 : Normal operation
1: De-emphasis all channels
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POWERDOWN MODE AND ADC/DAC DISABLE
Setting the PDWN register bit immediately powers down the DAC’s on the WM8772EFT, overriding
the DACD powerdown bits control bits. All trace of the previous input samples are removed, but all
control register settings are preserved. When PDWN is cleared the digital filters will be reinitialised
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0000010
Powerdown Control
2
PDWN
0
DESCRIPTION
Power Down all DAC’s Select:
0: All DAC’s enabled
1: All DAC’s disabled
The ADC and DACs may also be powered down individually by setting the ADCPD and DACPD
disable bits. Setting ADCD will disable the ADC and select a low power mode. The ADC digital filters
will be reset and will reinitialise when ADCPD is unset. Each Stereo DAC channel has a separate
disable DACPD[2:0]. Setting DACPD for a channel will disable the DACs and select a low power
mode. Resetting DACD will reinitialise the digital filters.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001010
Powerdown Control
0
ADCPD
0
ADC Disable:
0: Active
1: Disable
DESCRIPTION
3:1
DACPD [2:0]
000
DAC Disable
DACPD [2:0]
DAC CHANNEL 1
DAC CHANNEL 2
DAC CHANNEL 3
000
Active
Active
Active
001
DISABLE
Active
Active
010
Active
DISABLE
Active
011
DISABLE
DISABLE
Active
100
Active
Active
DISABLE
101
DISABLE
Active
DISABLE
110
Active
DISABLE
DISABLE
111
DISABLE
DISABLE
DISABLE
MASTER POWERDOWN
This control bit powers down the references for the whole chop. Therefore for complete powerdown,
both the ADC and DACs should be powered down first before setting this bit.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001010
Interface Control
4
PWRDNALL
0
DESCRIPTION
Master Power Down Bit:
0: Not powered down
1: Powered down
DAC MASTER MODE SELECT
Control bit DACMS selects between audio interface Master and Slave Modes. In Master mode
DACLRC and DACBCLK are outputs and are generated by the WM8772EFT. In Slave mode
DACCLRC, DACLRC and DACBCLK are inputs to WM8772EFT.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001010
Interface Control
5
DACMS
0
DESCRIPTION
DAC Audio Interface
Master/Slave Mode Select:
0: Slave Mode
1: Master Mode
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MASTER MODE DACLRC FREQUENCY SELECT
In Master mode the WM8772EFT generates DACLRC and DACBCLK. These clocks are derived
from the master clock and the ratio of DACMCLK to DACLRC is set by DACRATE.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001010
Interface Control
8:6
DACRATE [2:0]
010
DESCRIPTION
Master Mode
DACMCLK:DACLRC Ratio
Select:
000: 128fs
001: 192fs
010: 256fs
011: 384fs
100: 512fs
101: 768fs
ADC DIGITAL AUDIO INTERFACE CONTROL REGISTER
Interface format is selected via the ADCFMT[1:0] register bits:
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001011
Interface Control
1:0
ADCFMT[1:0]
00
DESCRIPTION
Interface Format Select
00: Right justified mode
01: Left justified mode
10: I2S mode
11: DSP mode A or B
The ADCIWL[1:0] bits are used to control the input word length.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0001011
Interface Control
3:2
ADCIWL[1:0]
00
Input Word Length
00: 16 bit data
01: 20 bit data
10: 24 bit data
11: 32 bit data
Note: 32-bit right justified mode is not supported.
In all modes, the data is signed 2's complement.
ADC MASTER MODE SELECT
Control bit ADCMS selects between audio interface Master and Slave Modes. In Master mode
ADCLRC and ADCBCLK are outputs and are generated by the WM8772EFT. In Slave mode
ADCLRC and ADCBCLK are inputs to WM8772EFT.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001011
Interface Control
4
ADCMS
0
DESCRIPTION
ADC Audio Interface
Master/Slave Mode Select:
0: Slave mode
1: Master mode
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MASTER MODE ADCLRC FREQUENCY SELECT
In Master mode the WM8772EFT generates ADCLRC and ADCBCLK. These clocks are derived
from the master clock and the ratio of ADCMCLK to ADCLRC is set by ADCRATE.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001011
ADCLRC and ADCBCLK
Frequency Select
7:5
ADCRATE [2:0]
010
DESCRIPTION
Master Mode
ADCMCLK:ADCLRC Ratio
Select:
010: 256fs
011: 384fs
100: 512fs
101: 768fs
ADC OVERSAMPLING RATE SELECT
For ADC operation at 96kHz it is recommended that the user set the ADCOSR bit. This changes the
ADC signal processing oversample rate to 64fs. The 64fs oversampling rate is only available in
modes were a 96KHz rate is supported, i.e. 256fs or 384fs. In all other modes the ADC will stay in a
128fs oversampling rate irrespective of what this bit is set to.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001011
ADC Oversampling Rate
8
ADCOSR
0
DESCRIPTION
ADC Oversampling Rate Select
0: 128x oversampling
1: 64x oversampling
ADC HIGHPASS FILTER DISABLE
The ADC digital filters contain a digital highpass filter. This defaults to enabled and can be disabled
using software control bit ADCHPD.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0001100
ADC Control
3
ADCHPD
0
ADC Highpass Filter Disable:
0: Highpass filter enabled
1: Highpass filter disabled
In left justified, right justified or I2S modes, the ADCLRP register bit controls the polarity of ADCLRC.
If this bit is set high, the expected polarity of ADCLRC will be the opposite of that shown in Figure
47, Figure 48, and Figure 49. Note that if this feature is used as a means of swapping the left and
right channels, a 1 sample phase difference will be introduced. In DSP modes, the ADCLRP register
bit is used to select between modes A and B.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001100
Interface Control
4
ADCLRP
0
DESCRIPTION
In Left/Right/I2S Modes:
ADCLRC Polarity (normal)
0: normal DACLRC polarity
1: inverted DACLRC polarity
In DSP Mode:
0: DSP mode A
1: DSP mode B
By default, DACLRC and DOUT are sampled on the rising edge of ADCBCLK and should ideally
change on the falling edge. Data sources that change ADCLRC and DOUT on the rising edge of
ADCBCLK can be supported by setting the ADCBCP register bit. Setting ADCBCP to 1 inverts the
polarity of ADCBCLK to the inverse of that shown in Figure 47 to Figure 57.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001100
Interface Control
5
ADCBCP
0
DESCRIPTION
ADCBCLK Polarity (DSP Modes):
0: normal BCLK polarity
1: inverted BCLK polarity
MUTE PIN DECODE
The MUTE pin can either be used an output or an input. When used as an input the MUTE pins
action can controlled by setting the DZFM bit to select the corresponding DAC for applying the MUTE
to. As an output its meaning is selected by the DZFM control bits. By default selecting the MUTE to
represent if DAC1 has received more than 1024 midrail samples will cause the MUTE to be asserted
a softmute on DAC1. Disabling the decode block will cause any logical high on the MUTE pin to
apply a softmute to all DACs.
REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001100
ADC Control
6
MPD
0
DESCRIPTION
MUTE Pin Decode Disable:
0: MUTE pin decode enable
1: MUTE pin decode disable
DAC TO ADC SYNC
If the DAC and ADC use the same MCLK, and they are operating in the same fs mode setting the
SYNC bit will improve performance by synchronising the internal clock between the two blocks.
Setting this at any other time may or may not improve or degrade the performance of the device.
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REGISTER ADDRESS
BIT
LABEL
DEFAULT
0001100
SYNC Control
7
SYNC
0
DESCRIPTION
SYNC Function:
0: Disable
1: Enable
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DAC DIGITAL VOLUME CONTROL
The DAC volume may also be adjusted in the digital domain using independent digital attenuation
control registers
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0000000
Digital
Attenuation
DACL1
7:0
LDA1[7:0]
11111111
(0dB)
Digital Attenuation data for Left channel DACL1 in 0.5dB steps. See
Table 11
8
UPDATE
Not latched
0000001
Digital
Attenuation
DACR1
7:0
RDA1[6:0]
11111111
(0dB)
8
UPDATE
Not latched
0000100
Digital
Attenuation
DACL2
7:0
LDA2[7:0]
11111111
(0dB)
8
UPDATE
Not latched
0000101
Digital
Attenuation
DACR2
7:0
RDA2[7:0]
11111111
(0dB)
8
UPDATE
Not latched
0000110
Digital
Attenuation
DACL3
7:0
LDA3[7:0]
11111111
(0dB)
8
UPDATE
Not latched
0000111
Digital
Attenuation
DACR3
7:0
RDA3[7:0]
11111111
(0dB)
8
UPDATE
Not latched
0001000
Master
Digital
Attenuation
(all channels)
7:0
MASTDA
[7:0]
11111111
(0dB)
8
UPDATE
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store LDA1 in intermediate latch (no change to output)
1: Store LDA1 and update attenuation on all channels
Digital Attenuation data for Right channel DACR1 in 0.5dB steps.
See Table 11
Controls simultaneous update of all Attenuation Latches
0: Store RDA1 in intermediate latch (no change to output)
1: Store RDA1 and update attenuation on all channels.
Digital Attenuation data for Left channel DACL2 in 0.5dB steps. See
Table 11
Controls simultaneous update of all Attenuation Latches
0: Store LDA2 in intermediate latch (no change to output)
1: Store LDA2 and update attenuation on all channels.
Digital Attenuation data for Right channel DACR2 in 0.5dB steps.
See Table 11
Controls simultaneous update of all Attenuation Latches
0: Store RDA2 in intermediate latch (no change to output)
1: Store RDA2 and update attenuation on all channels.
Digital Attenuation data for Left channel DACL3 in 0.5dB steps. See
Table 11
Controls simultaneous update of all Attenuation Latches
0: Store LDA3 in intermediate latch (no change to output)
1: Store LDA3 and update attenuation on all channels.
Digital Attenuation data for Right channel DACR3 in 0.5dB steps.
See Table 11
Controls simultaneous update of all Attenuation Latches
0: Store RDA3 in intermediate latch (no change to output)
1: Store RDA3 and update attenuation on all channels.
Digital Attenuation data for all DAC channels in 0.5dB steps. See
Table 11
Controls simultaneous update of all Attenuation Latches
0: Store gain in intermediate latch (no change to output)
1: Store gain and update attenuation on all channels.
L/RDAX[7:0]
ATTENUATION LEVEL
00(hex)
-∞ dB (mute)
01(hex)
-127dB
:
:
:
:
:
:
FE(hex)
-0.5dB
FF(hex)
0dB
Table 22 Digital Volume Control Attenuation Levels
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SOFTWARE REGISTER RESET
Writing to register 11111 will cause a register reset, resetting all register bits to their default values.
The device will be held in this reset state until a subsequent register write to any address is
completed.
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APPLICATIONS INFORMATION
RECOMMENDED EXTERNAL COMPONENTS
RECOMMENDED EXTERNAL COMPONENTS VALUES
COMPONENT
REFERENCE
SUGGESTED
VALUE
DESCRIPTION
De-coupling for DVDD and AVDD.
C1 and C5
10µF
C2 to C4
0.1µF
C8 and C9
1µF
C6 and C10
0.1µF
C7 and C11
10µF
C12
10µF
Filtering for VREFP. Omit if AVDD low noise.
R1
33Ω
Filtering for VREP. Use 0Ω if AVDD low noise.
De-coupling for DVDD and AVDD.
Analogue input high pass filter capacitors
Reference de-coupling capacitors for VMID and ADCREF pin.
Table 23 External Components Description
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SUGGESTED ANALOGUE LOW PASS POST DAC FILTERS
It is recommended that a lowpass filter be applied to the output from each DAC channel for Hi Fi applications. Typically a
second order filter is suitable and provides sufficient attenuation of high frequency components (the unique low order, high
bit count multi-bit sigma delta DAC structure used in WM8772EFT produces much less high frequency output noise than
normal sigma delta DACs. This filter is typically also used to provide the 2x gain needed to provide the standard 2Vrms
output level from most consumer equipment.
Figure 59 shows a suitable post DAC filter circuit, with 2x gain. Alternative inverting filter architectures might also be used
with as good results.
1.0nF
10uF
1.8kΩ
Ω
7.5kΩ
Ω
51Ω
Ω
VOUT1L
Ω
10kΩ
680pF
4.7kΩ
Ω
4.7kΩ
Ω
OP_FIL
VOUT1R
OP_FIL
VOUT2L
OP_FIL
VOUT2R
OP_FIL
VOUT3L
OP_FIL
VOUT3R
OP_FIL
Figure 59 Recommended Post DAC Filter Circuit
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To ensure that system ‘pop’ noise is kept to a minimum when power is applied or removed, a
transistor clamp circuit arrangement may be added to the output connectors of the system. A
recommended clamp circuit configuration is shown below.
Figure 60 Output Clamp Circuit
When the +VS power supply is applied, PNP transistor Q10 of the trigger circuit is held on until
capacitor C49 is fully charged. With transistor Q10 held ‘on’, NPN transistors Q4 to Q9 of the clamp
circuits are also switched on holding the system outputs near to GND. When capacitor C49 is fully
charged transistors Q10 and Q4 to Q9 are switched off setting the outputs active.
When the +VS power supply is removed, PNP transistor Q11 of the trigger circuit is switched on. In
turn, transistors Q4 to Q9 of the clamp circuits are switched on holding the outputs of the evaluation
board near to GND until the rest of the circuitry on the board has settled.
Note: It is recommended that low Vcesat switching transistors should be used in this circuit to ensure
that the clamp is applied before the rest of the circuitry has time to power down.
Important: If a trigger circuit such as the one shown is to be used, it is important that the +VS
supply drops quicker than any other supply to ensure that the outputs are clamped during the
period when ‘pop’ noise may occur.
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PACKAGE DIMENSIONS
FT: 32 PIN TQFP (7 x 7 x 1.0 mm)
b
DM028.A
e
24
17
25
16
E1
32
E
9
1
Θ
8
c
D1
D
L
A A2
A1
-Cccc C
Symbols
A
A1
A2
b
c
D
D1
E
E1
e
L
Θ
ccc
REF:
SEATING PLANE
Dimensions
(mm)
MIN
NOM
MAX
--------1.20
0.05
----0.15
0.95
1.00
1.05
0.30
0.37
0.45
0.09
----0.20
9.00 BSC
7.00 BSC
9.00 BSC
7.00 BSC
0.80 BSC
0.45
0.60
0.75
o
o
o
0
3.5
7
Tolerances of Form and Position
0.10
JEDEC.95, MS-026
NOTES:
A. ALL LINEAR DIMENSIONS ARE IN MILLIMETERS.
B. THIS DRAWING IS SUBJECT TO CHANGE WITHOUT NOTICE.
C. BODY DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSION, NOT TO EXCEED 0.25MM.
D. MEETS JEDEC.95 MS-026, VARIATION = ABA. REFER TO THIS SPECIFICATION FOR FURTHER DETAILS.
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WM8772EFT – 32 LEAD TQFP
IMPORTANT NOTICE
Wolfson Microelectronics plc (WM) reserve the right to make changes to their products or to discontinue any product or
service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing
orders, that information being relied on is current. All products are sold subject to the WM terms and conditions of sale
supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation
of liability.
WM warrants performance of its products to the specifications applicable at the time of sale in accordance with WM’s
standard warranty. Testing and other quality control techniques are utilised to the extent WM deems necessary to support
this warranty. Specific testing of all parameters of each device is not necessarily performed, except those mandated by
government requirements.
In order to minimise risks associated with customer applications, adequate design and operating safeguards must be used
by the customer to minimise inherent or procedural hazards. Wolfson products are not authorised for use as critical
components in life support devices or systems without the express written approval of an officer of the company. Life
support devices or systems are devices or systems that are intended for surgical implant into the body, or support or
sustain life, and whose failure to perform when properly used in accordance with instructions for use provided, can be
reasonably expected to result in a significant injury to the user. A critical component is any component of a life support
device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or
system, or to affect its safety or effectiveness.
WM assumes no liability for applications assistance or customer product design. WM does not warrant or represent that
any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual
property right of WM covering or relating to any combination, machine, or process in which such products or services might
be or are used. WM’s publication of information regarding any third party’s products or services does not constitute WM’s
approval, license, warranty or endorsement thereof.
Reproduction of information from the WM web site or datasheets is permissible only if reproduction is without alteration and
is accompanied by all associated warranties, conditions, limitations and notices. Representation or reproduction of this
information with alteration voids all warranties provided for an associated WM product or service, is an unfair and deceptive
business practice, and WM is not responsible nor liable for any such use.
Resale of WM’s products or services with statements different from or beyond the parameters stated by WM for that
product or service voids all express and any implied warranties for the associated WM product or service, is an unfair and
deceptive business practice, and WM is not responsible nor liable for any such use.
ADDRESS:
Wolfson Microelectronics plc
26 Westfield Road
Edinburgh
EH11 2QB
United Kingdom
Tel :: +44 (0)131 272 7000
Fax :: +44 (0)131 272 7001
Email :: [email protected]
w
PD Rev 4.2 October 2005
73