WM8740 Wolfson Microelectronics plc, WM8740 Datasheet - Page 24

• Manufacturer Part Number: WM8740
• Description: 24-bit, High Performance 192khz Stereo Dac
• Manufacturer: Wolfson Microelectronics plc

WM8740
APPLICATIONS INFORMATION
RECOMMENDED EXTERNAL COMPONENTS
Figure 25 External Components Diagram
RECOMMENDED EXTERNAL COMPONENTS VALUES
Table 21 External Components Description
w
COMPONENT
REFERENCE
Notes: 1.
C10 and C12
C9 and C11
C1 and C6
C7 and C8
C2 to C5
Audio Serial Data I/F
System Clock Input
R1
R2
Hardware Control
2. C
3.
Software I/F or
AGND and DGND should be connected as close to the WM8740 as possible.
Capacitor type used can have a big effect on device performance. It is
recommended that capacitors with very low ESR are used and that ceramics are
either NPO or COG type material to achieve best performance from the WM8740.
2
C
to
5
C
,
9
and C
SUGGESTED
1
1
should be positioned as close to the WM8740 as possible.
C
VALUE
DVDD
1
DGND
0.1μF
0.1μF
10kΩ
10μF
10μF
10μF
51Ω
+
C
2
R
R
2
2
28
27
26
23
22
24
25
8
7
4
6
1
2
3
5
DVDD
DGND
CSB/IWO
RSTB
DIFFHW
MODE
MUTEB
LRCIN
DIN
BCKIN
SCLK
MODE8X
ML/I2S
MC/DM1
MD/DM0
DESCRIPTION
De-coupling for DVDD and AVDD.
De-coupling for DVDD and AVDD.
Output AC coupling caps to remove VMID DC level from outputs.
Reference de-coupling capacitors for VMIDR and VMIDL.
Resistor to AVDD for open drain output operation.
Source termination resistors.
WM8740
VOUTRN
VOUTRP
VOUTLN
VOUTLP
AGNDR
VMIDR
AVDDR
AGNDL
AVDDL
VMIDL
AGND
ZERO
AVDD
15
20
14
10
19
21
11
18
16
17
13
12
9
C
C
3
9
AGND
C
C
1
0
4
-
+
-
+
AVDD
+
R
C
C
1
1
1
5
C
C
1
2
6
AVDD
AGND
+
+
LEFT OUTPUT DATA
RIGHT OUTPUT DATA
PD, Rev 4.3, August 2009
Production Data
24