El
ec
tri
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em
at
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M
32
F
4D
IS
C
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R
Y
34
/3
D
oc
ID
0
22
256
R
ev
2
Figur
e 1
4.
A
udio
STMicroelectronics
Title:
Number:
Rev:
Sheet of
B.2(PCB.SCH)
Date:
1/9/2012
MB997
4
6
STM32F4DISCOVERY Audio
PA4
PC12
PC10
R43
10K
PB6
PB9
R61
51
PD4
PC7
3V
I2C address 0x94
C50
1uF (X7R)
C59
1uF
C53
0.1uF
C47
1uF(X7R)
C41
0.1uF
C40
0.1uF
2V5
C42
0.1uF
3V
C56
1uF(X5R)
C57
1uF(X5R)
C48
150pF(COG)
C46
150pF(COG)
C45
0.1uF
C54
0.022uF
R62
51
C55
0.022uF
C43
0.1uF
Audio_RST
R47
100
C44
1uF(X7R)
Audio_SDA
Audio_SCL
I2S3_MCK
I2S3_WS
I2S3_SCK
I2S3_SD
Audio_DAC_OUT
C51
1uF(X7R)
PDM_OUT
R53
100
R52
100K
R44
100K
C52
10nF R54
1.2K
3V
CLK_IN
PDM_OUT
C60
100nF
C58
10uF
R63
0
R64
0
3V
1
3
2
CN4
ST-225-02
PC3
PA4
PC3
PB10
PC3
PB10
PB6
PB9
PC7
PC10
PC12
PA4
PD4
PC4
PC4
R48
0
R55
0
R49
0
R65
0
Not Fitted
Not Fitted
SDA
1
SCL
2
A0
3
SP
4
VP
5
SPKR_OUTA-
6
SP
7
VP
8
SPKR_OUTB-
9
-VHPFILT
10
FLYN
11
FLYP
12
+VHP
13
HP/LINE_OUTB
14
HP/LINE_OUTA
15
VA
16
AGND
17
FILT+
18
VQ
19
TSTO
20
AIN4A
21
AIN4B
22
AIN3A
23
AIN3B
24
AIN2A
25
AIN2B
26
AFILTA
27
AFILTB
28
AIN1A
29
AIN1B
30
SPKR/HP
31
RESET
32
VL
33
VD
34
DGND
35
TSTO
36
MCLK
37
SCLK
38
SDIN
39
LRCK
40
GND/Thermal Pad
41
U7
CS43L22
GND
1
GND
3
LR
2
CLK
4
VDD
6
DOUT
5
U9
MP45DT02
