WOLFSON WM8762ED

WM8762
24-bit 192kHz Stereo DAC
DESCRIPTION
FEATURES
The WM8762 is a high performance stereo DAC designed
for audio applications such as DVD, home theatre systems,
and digital TV. The WM8762 supports data input word
lengths from 16 to 24-bits and sampling rates up to 192kHz.
The WM8762 consists of a serial interface port, digital
interpolation filters, multi-bit sigma delta modulators and
stereo DAC in a very small 8-pin SOIC package.
The WM8762 supports a 16-24-bit left justified digital audio
interface.
The WM8762 is an ideal device to interface to AC-3,
DTS, and MPEG audio decoders for surround sound
applications, or for use in DVD players, including supporting
the implementation of 2 channels at 192kHz for high-end
DVD-Audio applications.
•
•
Stereo DAC
Audio Performance
•
98dB SNR (‘A’ weighted @ 48kHz)
-84dB THD
Sampling Frequency: 8kHz – 192kHz
•
•
Audio Data Interface Format
16-24-Bit Left Justified
2.7V – 5.5V Supply Operation
•
8-pin SOIC Package
APPLICATIONS
•
•
•
DVD Players
Digital TV
Digital Set Top Box
BLOCK DIAGRAM
BCKIN
LRCIN
SIGMA
DELTA
MODULATOR
MUTE
VOUTR
LEFT
DAC
VOUTL
DIGITAL
FILTERS
SERIAL
INTERFACE
DIN
RIGHT
DAC
SIGMA
DELTA
MODULATOR
MUTE
W
WM8762
MCLK
WOLFSON MICROELECTRONICS plc
www.wolfsonmicro.com
VDD
GND
Preliminary Technical Data, August 2003, Rev 2.0
Copyright 2003 Wolfson Microelectronics plc
WM8762
Preliminary Technical Data
TABLE OF CONTENTS
DESCRIPTION ............................................................................................................1
FEATURES..................................................................................................................1
APPLICATIONS ..........................................................................................................1
BLOCK DIAGRAM ......................................................................................................1
PIN CONFIGURATION................................................................................................3
ORDERING INFORMATION .......................................................................................3
PIN DESCRIPTION .....................................................................................................3
ABSOLUTE MAXIMUM RATINGS..............................................................................4
DC ELECTRICAL CHARACTERISTICS .....................................................................5
ELECTRICAL CHARACTERISTICS ...........................................................................5
TERMINOLOGY ................................................................................................................. 6
MASTER CLOCK TIMING .................................................................................................. 7
DIGITAL AUDIO INTERFACE ............................................................................................ 7
DEVICE DESCRIPTION..............................................................................................8
GENERAL INTRODUCTION .............................................................................................. 8
DAC CIRCUIT DESCRIPTION ........................................................................................... 8
CLOCKING SCHEMES ...................................................................................................... 9
DIGITAL AUDIO INTERFACE ............................................................................................ 9
AUDIO DATA SAMPLING RATES...................................................................................... 9
DIGITAL FILTER CHARACTERISTICS.............................................................................10
DAC FILTER RESPONSES...............................................................................................10
TYPICAL PERFORMANCE.......................................................................................11
RECOMMENDED EXTERNAL COMPONENTS .......................................................12
RECOMMENDED EXTERNAL COMPONENTS VALUES .................................................12
RECOMMENDED ANALOGUE LOW PASS FILTER (OPTIONAL) .........................13
PCB LAYOUT RECOMMENDATIONS ..............................................................................13
PACKAGE DRAWING...............................................................................................14
IMPORTANT NOTICE ...............................................................................................15
ADDRESS: ........................................................................................................................15
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WM8762
Preliminary Technical Data
PIN CONFIGURATION
DIN
1
8
VOUTL
BCKIN
2
7
VDD
LRCIN
3
6
GND
MCLK
4
5
VOUTR
WM8762
ORDERING INFORMATION
DEVICE
TEMP. RANGE
PACKAGE
MOISTURE
SENSITIVITY LEVEL
WM8762ED
-25 to +85oC
8-pin SOIC
MSL1
PIN DESCRIPTION
PIN
NAME
TYPE
Digital input
DESCRIPTION
1
DIN
Serial audio data input
2
BCKIN
Digital input
Bit clock input
3
LRCIN
Digital input
Sample rate clock input
4
MCLK
Digital input
System master clock input
5
VOUTR
Analogue output
Right channel DAC output
6
GND
Supply
Analogue ground supply
7
VDD
Supply
Positive supply
8
VOUTL
Analogue output
Left channel DAC output
Note:
Digital input pins have Schmitt trigger input buffers.
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Preliminary Technical Data
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-020A 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.
CONDITION
Supply voltage
Voltage range digital inputs
MIN
MAX
-0.3V
+7V
GND -0.3V
VDD +0.3V
Master Clock Frequency
50MHz
Operating temperature range, TA
-25°C
+85°C
Storage temperature after soldering
-65°C
+150°C
Package body temperature (soldering 10 seconds)
+240°C
Package body temperature (soldering 2 minutes)
+183°C
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Preliminary Technical Data
DC ELECTRICAL CHARACTERISTICS
PARAMETER
SYMBOL
Supply range
VDD
Ground
GND
TEST CONDITIONS
MIN
TYP
2.7
MAX
UNIT
5.5
V
0
V
26
mA
Supply current
VDD = 5V
Supply current
VDD = 3.3V
20
mA
Power down current (note 3)
VDD=3.3V
0.5
mA
ELECTRICAL CHARACTERISTICS
Test Conditions
VDD = 5V, GND = 0V, TA = +25oC, fs = 48kHz, MCLK = 256fs unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
0.8
V
0.10 x VDD
V
Digital Logic Levels (TTL Levels)
Input LOW level
VIL
Input HIGH level
VIH
Output LOW
VOL
IOL = 2mA
Output HIGH
VOH
IOH = 2mA
2
V
0.9 x VDD
V
DAC Output (Load = 10k ohms. 50pF)
0dBFS Full scale output voltage
SNR (Note 1,2)
SNR (Note 1,2)
SNR (Note 1,2)
SNR (Note 1,2)
SNR (Note 1,2)
SNR (Note 1,2)
THD
Dynamic range (Note 2)
At DAC outputs
1.2 x
VDD/5
98
A-weighted,
@ fs = 48kHz
A-weighted
@ fs = 96kHz
A-weighted
@ fs = 192kHz
A-weighted,
@ fs = 48kHz
VDD = 3.3V
A-weighted
@ fs = 96kHz
VDD = 3.3V
Non ‘A’ weighted @ fs
= 48kHz
1kHz, 0dBFS
1kHz, THD+N @
-60dBFs
90
Vrms
dB
95
dB
92
dB
95
dB
95
dB
92
dB
-84
dB
98
dB
1.2
VRMS
0.79
VRMS
±1
%FSR
1
kohms
1
kohms
Analogue Output Levels
Output level
Load = 10k ohms,
0dBFS
Load = 10k ohms,
0dBFS,
(VDD = 3.3V)
Gain mismatch
channel-to-channel
Minimum resistance load
Maximum capacitance load
Output d.c. level
To midrail or a.c.
coupled
To midrail or a.c.
coupled
(VDD = 3.3V)
5V or 3.3V
100
pF
VDD/2
V
1.8
V
Power On Reset (POR)
POR threshold
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Preliminary Technical Data
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
over a 20Hz to 20kHz bandwidth.
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. Power down occurs 1.5µs after MCLK stops.
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.
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Preliminary Technical Data
MASTER CLOCK TIMING
tMCLKL
MCLK
tMCLKH
tMCLKY
Figure 1 Master Clock Timing Requirements
Test Conditions
o
VDD = 5V, GND = 0V, TA = +25 C, fs = 48kHz, MCLK = 256fs unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
System Clock Timing Information
MCLK Master clock pulse width high
tMCLKH
8
ns
MCLK Master clock pulse width low
tMCLKL
8
ns
MCLK Master clock cycle time
tMCLKY
20
MCLK Duty cycle
Time from MCLK stopping to power
down.
ns
40:60
60:40
1.5
12
µs
MAX
UNIT
DIGITAL AUDIO INTERFACE
tBCH
tBCL
BCKIN
tBCY
LRCIN
tDS
tLRH
tLRSU
DIN
tDH
Figure 2 Digital Audio Data Timing
Test Conditions
VDD = 5V, GND = 0V, TA = +25oC, fs = 48kHz, MCLK = 256fs unless otherwise stated.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
Audio Data Input Timing Information
BCKIN cycle time
tBCY
40
ns
BCKIN pulse width high
tBCH
16
ns
BCKIN pulse width low
tBCL
16
ns
LRCIN set-up time to BCKIN rising
edge
tLRSU
8
ns
LRCIN hold time from BCKIN rising
edge
tLRH
8
ns
DIN set-up time to BCKIN rising edge
tDS
8
ns
DIN hold time from BCKIN rising edge
tDH
8
ns
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WM8762
Preliminary Technical Data
DEVICE DESCRIPTION
GENERAL INTRODUCTION
The WM8762 is a high performance DAC designed for digital consumer audio applications. The
range of features make it ideally suited for use in DVD players, AV receivers and other
consumer audio equipment.
The WM8762 is a complete 2-channel stereo audio digital-to-analogue converter, including
digital interpolation filter, multi-bit sigma delta with dither, and switched capacitor multi-bit
stereo DAC and output smoothing filters. It is fully compatible and an ideal partner for a range
of industry standard microprocessors, controllers and DSPs. A novel multi bit sigma-delta DAC
design is used, utilising a 128x oversampling rate to optimise signal to noise performance and
offer increased clock jitter tolerance. (In ‘high-rate’ operation, the oversampling ratio is 64x for
system clocks of 128fs or 192fs)
Operation using master clocks of 256fs, 384fs, 512fs or 768fs is provided, selection between
clock rates being automatically controlled. Sample rates (fs) from less than 8kHz to 192KHz
are allowed, provided the appropriate system clock is input.
The audio data interface supports a 16-24-bit left justified interface format. A single 2.7-5.5V
supply may be used, the output amplitude scaling with absolute supply level. Low supply
voltage operation and low current consumption combined with the low pin count small package
make the WM8762 attractive for many consumer applications.
The device is packaged in a small 8-pin SOIC.
DAC CIRCUIT DESCRIPTION
The WM8762 DAC is designed to allow playback of 24-bit PCM audio or similar data with high
resolution and low noise and distortion. Sample rates up to 192kHz may be used, with much
lower sample rates acceptable provided that the ratio of sample rate (LRCIN) to system master
clock (MCLK) is maintained at one of the required rates.
The two DACs on the WM8762 are implemented using sigma-delta oversampled conversion
techniques. These require that the PCM samples are digitally filtered and interpolated to
generate a set of samples at a much higher rate than the input rate. This sample stream is then
digitally modulated to generate a digital pulse stream that is then converted to analogue signals
in a switched capacitor DAC. The advantage of this technique is that the DAC is linearised
using noise shaping techniques, allowing the 24-bit resolution to be met using non-critical
analogue components. A further advantage is that the high sample rate at the DAC output
means that smoothing filters on the output of the DAC need only have fairly crude
characteristics in order to remove the characteristic steps, or images, on the output of the DAC.
To ensure that generation of tones characteristic to sigma-delta converters is not a problem,
dithering is used in the digital modulator and a higher order modulator is used. The multi-bit
switched capacitor technique used in the DAC reduces sensitivity to clock jitter, and
dramatically reduces out of band noise compared to switched current or single bit techniques
used in other implementations.
The outputs of the 2 DACs are buffered out of the device by buffer amplifiers. These amplifiers
will source load currents of several mA and sink current up to 1.5mA allowing significant loads
to be driven. The output source is active and the sink is Class A, i.e. fixed value, so greater
loads might be driven if an external ‘pull-down’ resistor is connected at the output.
Typically an external low pass filter circuit will be used to remove residual out of band noise
characteristic of delta sigma converters. However, the advanced multi-bit DAC used in
WM8762 produces far less out of band noise than single bit traditional sigma delta DACs, and
so in many applications this filter may be removed, or replaced with a simple RC pole.
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WM8762
Preliminary Technical Data
CLOCKING SCHEMES
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 clock can be applied directly through the
MCLK input pin with no configuration necessary for sample rate selection.
Note that on the WM8762, MCLK is used to derive clocks for the DAC path. The DAC path
consists of DAC sampling clock, DAC digital filter clock and DAC digital audio interface timing.
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 DAC.
The device can be powered down by stopping MCLK. In this state the power consumption is
substantially reduced.
DIGITAL AUDIO INTERFACE
WM8762 supports the left justified audio interface format. The WM8762 supports word lengths
of 16-24 bits (MSB first). The word length may be any value up to 24-bits. (If the word length
shorter than 24-bits is used, the unused bits will be padded with zeros).
In left justified mode, the MSB of DIN is sampled by the WM8762 on the first rising edge of
BCKIN following a LRCIN transition. LRCIN is high during the left samples and low during the
right samples.
1/fs
LEFT CHANNEL
RIGHT CHANNEL
LRCIN
BCKIN
DIN
1
2
3
n-2 n-1
n
MSB
1
LSB
2
3
n-2 n-1
MSB
n
LSB
Figure 3 Left Justified Mode Timing Diagram
AUDIO DATA SAMPLING RATES
The master clock for WM8762 supports audio sampling rates from 128fs to 768fs, where fs is
the audio sampling frequency (LRCIN) typically 32kHz, 44.1kHz, 48kHz, 96kHz or 192kHz. The
master clock is used to operate the digital filters and the noise shaping circuits.
The WM8762 has a master clock detection circuit that automatically determines the relation
between the master clock frequency and the sampling rate (to within +/- 8 master clocks). If
there is a greater than 8 clocks error, the interface shuts down the DAC and mutes the output.
The master clock should be synchronised with LRCIN, although the WM8762 is tolerant of
phase differences or jitter on this clock.
SAMPLING
RATE
(LRCIN)
32kHz
44.1kHz
48kHz
96kHz
192kHz
MASTER CLOCK FREQUENCY (MHZ) (MCLK)
128fs
192fs
256fs
384fs
512fs
768fs
4.096
5.6448
6.114
12.288
24.576
6.144
8.467
9.216
18.432
36.864
8.192
11.2896
12.288
24.576
Unavailable
12.288
16.9340
18.432
36.864
Unavailable
16.384
22.5792
24.576
Unavailable
Unavailable
24.576
33.8688
36.864
Unavailable
Unavailable
Table 1 Master Clock Frequencies Versus Sampling Rate
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Preliminary Technical Data
DIGITAL FILTER CHARACTERISTICS
PARAMETER
SYMBOL
TEST CONDITIONS
Passband Edge
-3dB
Passband Ripple
f < 0.444fs
Stopband Attenuation
f > 0.555fs
MIN
TYP
MAX
UNIT
0.487fs
±0.05
dB
-60
dB
Table 2 Digital Filter Characteristics
DAC FILTER RESPONSES
0.2
0
0.15
-20
-40
Response (dB)
Response (dB)
0.1
-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 4 DAC 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 5 DAC Digital Filter Ripple -44.1, 48 and 96kHz
-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
1
Figure 6 DAC Digital Filter Frequency Response – 192kHz
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0
0.05
0.1
0.15
0.2
0.25
0.3
Frequency (Fs)
0.35
0.4
0.45
0.5
Figure 7 DAC Digital Filter Ripple –192kHz
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WM8762
Preliminary Technical Data
TYPICAL PERFORMANCE
-65
-70
-75
-80
-85
d
B
r
-90
-95
B
-100
-105
-110
-115
-120
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
+0
dBFS
Figure 8 WM8762 Functionality THD+N VDD = 5V
-70
-72.5
-75
-77.5
-80
-82.5
-85
-87.5
-90
d
B
r
B
-92.5
-95
-97.5
-100
-102.5
-105
-107.5
-110
-112.5
-115
-117.5
-120
-160
-150
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
+0
dBFS
Figure 9 WM8762 Functionality THD+N VDD = 3V
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WM8762
Preliminary Technical Data
RECOMMENDED EXTERNAL COMPONENTS
VDD
7
+
C1
VDD
C2
6
GND
AGND
VOUTR
WM8762
3
4
2
Audio Serial Data I/F
1
VOUTL
5
8
C3
+
C4
AC-Coupled
VOUTR/L
to External LPF
+
LRCIN
MCLK
BCKIN
DIN
1. C2 should be positioned as close to the WM8762 as possible.
Notes:
2. Capacitor types should be carefully chosen. Capacitors with very low ESR are
recommended for optimum performance.
3. C3 and C4 not required if using the recommended low pass filter in Figure 9.
Figure 10 External Component Diagram
RECOMMENDED EXTERNAL COMPONENTS VALUES
COMPONENT
REFERENCE
SUGGESTED
VALUE
DESCRIPTION
C1
10µF
De-coupling for VDD
C2
0.1µF
De-coupling for VDD
C3 and C4
10µF
Output AC coupling caps to remove midrail DC level from outputs
Table 3 External Components Description
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WM8762
Preliminary Technical Data
RECOMMENDED ANALOGUE LOW PASS FILTER (OPTIONAL)
4.7kΩ
4.7kΩ
+VS
_
51Ω
10uF
+
1.8kΩ
7.5KΩ
+
1.0nF
680pF
-VS
47kΩ
Figure 11 Recommended Low Pass Filter (Optional)
An external low pass filter is recommended (see Figure 20) if the device is driving a wideband
amplifier. In some applications, a passive RC filter may be adequate.
PCB LAYOUT RECOMMENDATIONS
Care should be taken in the layout of the PCB that the WM8726 is to be mounted to. The
following notes will help in this respect:
1.
The VDD supply to the device should be as noise free as possible. This can be
accomplished to a large degree with a 10uF bulk capacitor placed locally to the device and a
0.1uF high frequency decoupling capacitor placed as close to the VDD pin as possible. It is
best to place the 0.1uF capacitor directly between the VDD and GND pins of the device on
the same layer to minimize track inductance and thus improve device decoupling
effectiveness.
2.
Separate analogue and digital track routing from each other. The device is split into
analogue (pins 5 – 9) and digital (pins 1 – 4 & pins 10 – 14) sections that allow the routing of
these signals to be easily separated. By physically separating analogue and digital signals,
crosstalk from the PCB can be minimized.
3.
Use an unbroken solid GND plane. To achieve best performance from the device, it is
advisable to have either a GND plane layer on a multilayer PCB or to dedicate one side of a
2 layer PCB to be a GND plane. For double sided implementations it is best to route as
many signals as possible on the device mounted side of the board, with the opposite side
acting as a GND plane. The use of a GND plane greatly reduces any electrical emissions
from the PCB and minimizes crosstalk between signals.
An evaluation board is available for the WM8726 that demonstrates the above techniques and
the excellent performance achievable from the device. This can be ordered or the User manual
downloaded from the Wolfson web site at www.wolfsonmicro.com
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WM8762
Preliminary Technical Data
PACKAGE DRAWING
D: 8 PIN SOIC 3.9mm Wide Body
DM009.B
B
e
8
5
E
1
H
L
4
D
h x 45o
A
A1
-C-
0.10 (0.004)
Symbols
A
A1
B
C
D
e
E
h
H
L
α
Dimensions
(mm)
MIN
MAX
1.35
1.75
0.10
0.25
0.33
0.51
0.19
0.25
4.80
5.00
1.27 BSC
3.80
4.00
0.25
0.50
5.80
6.20
0.40
1.27
0o
8o
REF:
α
C
SEATING PLANE
Dimensions
(Inches)
MIN
MAX
0.0532
0.0688
0.0040
0.0098
0.0130
0.0200
0.0075
0.0098
0.1890
0.1968
0.050 BSC
0.1497
0.1574
0.0099
0.0196
0.2284
0.2440
0.0160
0.0500
0o
8o
JEDEC.95, MS-012
NOTES:
A. ALL LINEAR DIMENSIONS ARE IN MILLIMETERS (INCHES).
B. THIS DRAWING IS SUBJECT TO CHANGE WITHOUT NOTICE.
C. BODY DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSION, NOT TO EXCEED 0.25MM (0.010IN).
D. MEETS JEDEC.95 MS-012, VARIATION = AA. REFER TO THIS SPECIFICATION FOR FURTHER DETAILS.
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Preliminary Technical Data
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
20 Bernard Terrace
Edinburgh
EH8 9NX
United Kingdom
Tel :: +44 (0)131 272 7000
Fax :: +44 (0)131 272 7001
Email :: [email protected]
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