WM8738 EV1M Evaluation Board User Handbook

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WM8738 EV1M
WM8738 Evaluation Board User Handbook
INTRODUCTION
The WM8738 is a 24-bit Stereo ADC.
This evaluation platform and documentation should be used in conjunction with the latest version of
the WM8738 datasheet. The datasheet gives device functionality information as well as timing and
data format requirements.
This evaluation platform has been designed to allow the user ease of use and give optimum
performance in device measurement.
GETTING STARTED
PACKING LIST
The WM8738 Evaluation Kit Contains:
•
1 WM8738-EV1B Evaluation Board
•
This manual -1 WM8738-EV1M
CUSTOMER REQUIREMENTS
Minimum Customer Requires:
•
D.C. Power supply of +5V
•
D.C. Power supply of +3.0V to +5.5V
•
D.C. Power supply of +3.0V to +3.6V
•
D.C. Power supply of +12V and -12V
ADC Signal Path Requires (minimum):
•
Analogue coaxial jack plug data source
•
Digital coaxial data receiving unit
•
Master Clock source
WOLFSON MICROELECTRONICS LTD
www.wolfsonmicro.com
August 2002, Rev 2.1
Copyright 2002 Wolfson Microelectronics Ltd.
WM8738-EV1M
POWER SUPPLIES
Using appropriate power leads with 4mm connectors, +5V should be applied to the +5V panel socket
J1.
+3.0V to +3.6V should be applied to the DVDD panel socket J3 and +3.0V to +5.5V should be
applied to the AVDD panel socket J5.
+12V should be applied to the +12V panel socket J7 and -12V should be applied to the -12V panel
socket J10.
DGND should be connected to the DGND panel socket J2 and AGND to the AGND panel socket J6.
The DGND and AGND connections may be connected to a common GND on the supply with no
reduction in performance.
Note: Refer to WM8738 datasheet for limitations on individual supply voltages.
BOARD FUNCTIONALITY
There are three options for inputting the required digital clocks to the WM8738 evaluation board.
There is a coaxial input (J14) via a standard phono connector or a direct digital input is available via
one side of a 2x6 pin header (H1). A further option is to input a MCLK via connector J9 and use the
CPLD (U1) to generate BCLK and LRCLK.
The analogue input signals are applied to the evaluation board via phono connectors through either
passive or active anti-alias filters. For passive filtering J17 (LIN) and J16 (RIN) can be used and for
active filtering J12 (LIN) and J13 (RIN).
There are two options for outputting digital data from the WM8738 evaluation board. There is a
coaxial output (J8) via a standard phono connector or the digital signals output from the WM8738
may be accessed via one side of a 2x6 pin header (H2).
All WM8738 device pins are accessible for easy measurement via the 8 pin headers (J11 & J15)
running up each side of the device.
BOARD INPUT
Analogue input to the WM8738 is selectable via switches SW5 and SW6. This allows the analogue
input to either pass through a passive anti-aliasing filter, using J17 (LIN) and JI6 (RIN), or an active
anti-aliasing filter, using J12 (LIN) and J13 (RIN).
Digital clock signals must be supplied to the WM8738. A digital (AES/EBU, UEC958, S/PDIF, EIAJ
CP340/1201) signal input may be applied to the coaxial input (J14), allowing the CS8427 (U3) to
generate the necessary clocks. A direct digital input is also available via one side of a 2x6 pin
header (H1). There is also the facility to generate multi-rate clocks from U1 using SW7 as the rate
selection and either the MCLK from the CS8427 (U3) or an independent MCLK input to SMB
connector J9.
The digital inputs of the WM8738 are +5V tolerant (independent of supplies), however, a level shift IC
(U2) has been included in the audio interface signal path to buffer the input signals when applied via
header (H1) and minimise any performance degradation this may cause..
Note: The level shift IC's (U2 and U6) are set to shift from +5V to DVDD when shipped from Wolfson.
BOARD OUTPUT
The output interface from the board is via a coaxial (J8) digital (AES/EBU, UEC958, S/PDIF, EIAJ
CP340/1201) signal output. A direct signal output is available via one side of a 2x6 pin header (H2).
Data is output in one of the WM8738 supported formats - see datasheet.
A level shift IC (U6) has been included in the audio output interface path to provide signal buffering
when output signals are taken from 2x6 pin header H2 will meet external receiver requirements.
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
2
WM8738-EV1M
INTERFACES
1
2
3
4
J3
J2
ON
J1
KEY
0
1
J5
J6
1
3
5
7
9
11
J7
SW7
J10
2
4
6
8
10
12
SW4
H1
1
2
3
4
5
6
7
8
1
SW8
SW9
J9
J11
1
1
1
1
SW1
SW6
1
2
4
OPEN
3
1
2
3
5
1
0
6
1
J15
SW5
1
1
SW3
H2
SW2
Figure 1 Interfaces
HEADERS
H1
SIGNAL
J15
1
WM8738
1
SIGNAL
GND
SLAVE_LRC
GND
2
3
4
2
3
4
SDOUT
BCLK
FMT
9/10
11/12
SLAVE_BCLK
GND
5
6
7
5
6
7
CAP
VREF
RIN
H2
12/11
10/9
SIGNAL
8
10
AGND
GND
SDOUT
1/2
MCLK
3/4
5/6
7/8
DVDD
J11
WM8738
SIGNAL
8/7
6/5
4/3
GND
BCLK_OUT
GND
1
2
3
8
9
10
LIN
AVDD
AGND
2/1
ADC_LRCLK
4
5
6
11
12
13
NOHP
LRCLK
MCLK
7
8
14
14
DGND
DGND
Table 1 Headers
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
3
WM8738-EV1M
LINKS
LINKS & JUMPERS
DESCRIPTION
SW3
(FMT)
Pins 1 & 2 SHORT – Left Justified mode
Pins 2 & 3 SHORT – I2S mode
SW4
(NOHP)
Pins 1 & 2 SHORT – Digital HPF Disabled
Pins 2 & 3 SHORT – Digital HPF Enabled
SW5
Pins 1 & 2 SHORT – Active anti-alias filter input selected
Pins 2 & 3 SHORT – RC filter only selected
SW6
Pins 1 & 2 SHORT – Active anti-alias filter input selected
Pins 2 & 3 SHORT – RC filter only selected
SW8
Pins 1 & 2 SHORT – Standard CS8427 BCLK selected
Pins 2 & 3 SHORT – Multi-rate BCLK selected
SW9
Pins 1 & 2 SHORT – Standard CS8427 LRCLK selected
Pins 2 & 3 SHORT – Multi-rate LRCLK selected
J9
External multi-rate MCLK input
Table 2 Links
SWITCHES
SWITCH
SW1
(DATA FORMAT)
SW2
SW7
(MCLK RATE)
DESCRIPTION
6
0
0
5
0
0
4
1
0
3
0
0
2
0
0
1
1
1
DATA FORMAT
I2S Compatible
Left Justified
The CS8427 may be RESET by pressing and releasing switch SW2. This is
required if the switches on SW1 are changed after the board is powered up.
4
1
0
0
0
3
0
1
0
0
2
0
0
1
0
1
0
0
0
1
MCLK RATE
256fs
384fs
512fs
768fs
Table 3 Switches
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
4
WM8738-EV1M
WM8738 OPERATION
STANDARD CONTROL & USING MULTI-RATE MCLK
The WM8738 is a hardware control only device and must be dealt with as a slave (i.e. all clocks must
be supplied to the WM8738 from another source).
There are only 2 pins that can be used to change the setup of the WM8738, these are pin 4 (FMT)
and pin 11 (NOHP). 3 pin link switch SW3 is used to control the FMT pin, putting this switch high
(short pins 1 & 2) will set the output data format from the WM8738 to Left Justified mode while
putting the switch low (short pins 2 & 3) will set the output data format to I2S mode. 3 pin link switch
SW4 is used to control the NOHP pin, putting this switch high (short pins 1 & 2) will disable the
internal digital High Pass Filter while putting the switch low (short pins 2 & 3) will enable the internal
digital High Pass Filter.
Figure 2 shows the basic ‘getting started’ setup required to operate the board. In this example the
data format is set to I2S with the digital HPF set active.
J2
J3
3
J1
2
DGND
AVDD
+3.0V
to
+5.5V AGND
1
+5V
DVDD
+3.0V
to
+3.6V
0
1
J5
J6
4
ON
SW7
J7
+12V
J10
-12V
H1
SW4
J18
1
SPDIF_
OUT
SW8
SW9
J9
J17
LIN
J11
1
1
1
1
SW1
SW6
1
2
LIN
J13
RIN
J16
RIN
4
OPEN
3
J12
5
1
0
6
1
SPDIF_
IN
J14
H2
1
(required to
provideWM8738
Clocks)
SW5
1
SW3
J15
SW2
Figure 2 Basic Setup Example
LINKS & JUMPERS
DESCRIPTION
H1
All Links ON
H2
All Links ON
SW3 (FMT)
Pins 2 & 3 SHORT – I2S mode
SW4 (NOHP)
Pins 2 & 3 SHORT – Digital HPF Enabled
SW5
Pins 1 & 2 SHORT – Active anti-alias filter input selected
SW6
Pins 1 & 2 SHORT – Active anti-alias filter input selected
SW8
Pins 1 & 2 SHORT – Standard CS8427 BCLK selected
SW9
Pins 1 & 2 SHORT – Standard CS8427 LRCLK selected
Table 4 Basic Setup Example Settings
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
5
WM8738-EV1M
An additional feature that has been provided on the WM8738 evaluation board is the ability to run
with multi-rate MCLK’s. This is achieved through the use of the CPLD (U1) and the relevant switch
setting of SW7. Four MCLK rates are supported, 256fs, 384fs, 512fs and 768fs. To operate the
evaluation board in this mode, 3 pin jumper switches SW8 and SW9 should be set so that pins 2 and
3 are shorted, an external MCLK should be supplied through the SMB connector J9, the MCLK is
then passed through the CPLD which divides it down to generate the equivalent LRCLK and BCLK
frequencies.
Figure 3 shows the setup required if using an external MCLK. In this example the data format is set
to I2S digital HPF is active and the MCLK is running at 512fs.
J2
J3
3
J1
2
DGND
AVDD
+3.0V
to
+5.5V AGND
1
+5V
DVDD
+3.0V
to
+3.6V
0
1
J5
J6
4
ON
SW7
MCLK
+12V
J10
-12V
SW8
SW9
J9
H1
SW4
J18
1
SPDIF_
OUT
J7
J17
LIN
J11
1
SW6
1
1
1
SW1
1
J12
LIN
2
4
OPEN
3
5
1
0
6
J13
J14
OUT
J16
RIN
1
H2
SW3
J15
SPDIF_
IN
RIN
SW5
1
1
SW2
Figure 3 Using an External MCLK Example
LINKS & JUMPERS
DESCRIPTION
H1
All Links OFF
H2
All Links ON
SW3
(FMT)
Pins 2 & 3 SHORT – I2S mode
SW4
(NOHP)
Pins 2 & 3 SHORT – Digital HPF Enabled
SW5
Pins 1 & 2 SHORT – Active anti-alias filter input selected
SW6
Pins 1 & 2 SHORT – Active anti-alias filter input selected
SW8
Pins 2 & 3 SHORT – Multi-rate BCLK selected
SW9
Pins 2 & 3 SHORT – Multi-rate LRCLK selected
J9
External multi-rate MCLK input
Table 5 Using an External MCLK Example Settings
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
6
WM8738-EV1M
WM8738-EV1B SCHEMATIC
Figure 4 Functional Diagram
Figure 5 Digital Interface
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
7
WM8738-EV1M
Figure 6 Analogue Input
Figure 7 Level Shift / Buffer
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
8
WM8738-EV1M
Figure 8 Multi-Rate Generator
Figure 9 WM8738
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
9
WM8738-EV1M
Figure 10 Power
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
10
WM8738-EV1M
WM8738-EV1B PCB LAYOUT
Figure 11 Top Layer Silkscreen
Figure 12 Top Layer
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
11
WM8738-EV1M
Figure 13 Bottom Layer
Figure 14 Bottom Layer Silkscreen
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
12
WM8738-EV1M
WM8738-EV1B BILL OF MATERIAL
Description
REF-DES
QTY
10uF 6.3 Dia 2.5 pitch Oscon Through Hole Cap. 16V 20%
C4 C6-7 C9 C13 C17 C51 C55-56
1uF 4 Dia 2 pitch Oscon Through Hole Cap. 25V 20%
C22 C48
9
2
0.01uF 0805 SMD Ceramic Capacitor 50V X7R
0.1uF 0805 SMD Ceramic Capacitor 50V X7R
C50
C1-3 C5 C8 C10-12 C14 C16 C18-20 C23 C27
C32-38 C40 C43-44
1
25
180pF 0805 SMD Ceramic Capacitor 50V NPO
C29 C41
2
1nF 0805 SMD Ceramic Capacitor 50V NPO
C24 C39
2
220pF 0805 SMD Ceramic Capacitor 50V X7R
C31 C47 C58 C59
4
820pF 0805 SMD Ceramic Capacitor 50V NPO
C30 C46
2
82nF 0805 SMD Ceramic Capacitor 25V X7R
C49
1
1uF 1206 SMD Ceramic Capacitor 16V X7R
C25 C52 C53 C61
4
2.2nF 1206 SMD Ceramic Capacitor 50V NPO
C42
1
4.7nF 1206 SMD Ceramic Capacitor 50V COG
C21 C26 C54 C62
4
2x5 2.54mm Male PCB Header LoPro VERTICAL
J4
1
1x8 2.54mm pitch PCB Pin Header VERTICAL
J11 J15
2
2x6 2.54mm pitch PCB Pin Header VERTICAL
H1-2
2
JSK9-16-G0 PCB 1x3 Jumper Switch 0.1" Center-off VERTICAL
SW3-6 SW8-9
6
4mm Non-Insulated Panel Socket 16A
J1-3 J5-7 J10
7
Phono Socket PCB mount BLACK
J8
1
Phono Socket PCB mount RED
J13 J16
2
Phono Socket PCB mount WHITE
J12 J17
2
Phono Socket PCB mount YELLOW
J14
1
SMB Connector PCB Mount 50 Ohm VERTICAL
J9
1
CD8427 96KHz Audio Transceiver
U3
1
DS1813 5V active Low Power-On-Reset chip SOT
U7
1
0R 1206 Resistor on 1210 Inductor site
L1-4 L6
5
3.3uH 1210 Surface Mount Inductor '1210A series'
L7
1
MC33078 Low Noise Dual Op-Amp SO
U5
1
0R 0805 SMD chip resistor 1% 0.1W
R2 R4 R5 R7 R12 R16 R42
7
100K 0805 SMD chip resistor 1% 0.1W
R20 R29 R39
3
10K 0805 SMD chip resistor 1% 0.1W
R1 R3 R6 R8 R21
5
47K 0805 SMD chip resistor 1% 0.1W
R13 R15 R17 R19 R23-24 R26 R30-33 R35
12
5k1 0805 SMD chip resistor 1% 0.125W
R34
1
620R 0805 SMD chip resistor 1% 0.1W
R11
1
680R 0805 SMD chip resistor 1% 0.1W
R22 R41 R45 R48
4
75R 0805 SMD chip resistor 1% 0.125W
R40
1
8K2 0805 SMD chip resistor 1% 0.1W
R25 R27-28 R36-38
6
SN74LVCC4245A Octal Dual Supply(5V, 3-5V) Transceiver SO
U2 U6
2
DIL Switch 4-Way Rocker
SW7
1
DIL Switch 6-Way Rocker
SW1
1
B3F1000 SPNO PCB mount switch
SW2
1
1.32mm PCB Test Terminal BLACK
TP1-6
6
2:1 Ratio 96KHz SPDIF Digital Audio transformer SOIC
T1
1
WM8738 Stereo ADC
U4
1
XC9536XL-15 3.3V 36 macrocell CPLD
U1
1
1
Note: The audio transformer (T1) used on this board is manufactured by Scientific Conversion
Inc. (www.scientificonversion.com).
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
13
WM8738-EV1M
EVALUATION SUPPORT
The aim of this evaluation kit is to help you to become familiar with the functionality and performance
of the WM8738, stereo audio ADC.
If you require more information or require technical support please contact Wolfson Microelectronics
Applications group through the following channels:
Email:
Apps. Telephone:
Fax:
Mail:
[email protected]
(+44) 131 272 7070
(+44) 131 272 7001
Applications at the address on the last page.
or contact your local Wolfson representative.
Additional information may be made available from time to time on our web site at:
http://www.wolfsonmicro.com
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
14
WM8738-EV1M
IMPORTANT NOTICE
Wolfson Microelectronics Ltd (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.
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 neither 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 neither responsible
nor liable for any such use.
ADDRESS:
Wolfson Microelectronics Ltd
20 Bernard Terrace
Edinburgh
EH8 9NX
United Kingdom
Tel :: +44 (0)131 272 7000
Fax :: +44 (0)131 272 7001
Email :: [email protected]
WOLFSON MICROELECTONICS LTD
Rev 2.1 August 2002
15