Schematics

D
C
A
B
123456
A
B
D
C
123456
MCU
OSC
Test
MIC
4054
LED
POWER
BAT
Earphone
KEY
1
DACVSS
2
NC
3
VDDIO
4
PB9/PB10/ADC9
5
PB8/AUX1R/ADC8
6
PB7/PB4/AUX1L/ADC7
7
VSSIO
8
NC
9
VBAT
10
LDO_IN/PB5
11
BT_AVDD
12
PB2
13
PB3/ADC6
14
PB1/ADC5
15
PB0
16
BT_RF
17
VSSIO
18
BT_OSCI
19
BT_OSCO
20
21
22
SD1DAT/PC3
23
NC
24
USBDM
25
ADC12/USBDP
26
ADC0/
A
U
X
0
R/MIC_BIAS/PA1/PC4
27
MIC/PC6
28
DACR
29
DACL
30
VCOMO
31
DACVDD
32
NC
33
GND
U1
AC6956A
C13 105/10V
C10105/16V
C1NC
C7105/16V
C4
2.7P
C14 105/16V
C2
105
C12 NC
1
2
E2
+
MIC2
C9 104
U5 3.4V~4.2V
1
VBUS
2
D-
3
D+
4
ID
5
GND
6
S
7
S
8
S
9
S
USB2
DM
DP
LED2
LED
BLED
LED1
LED
RLED
4
VCC
1
CHRG
5
PROG
3
BAT
2
GND
S1
NC
R1
NC
C11
NC
C18
120nH
R20
120nH
R5 120nH
R3
2.7R
T3
VBAT4.2V
C5
NC
C3
NC
1 2
Y2
24MHZ
R2
0R
L+
L-
R-
R+
2
4
3
1
J1
AUX
K6
POWER
TVS1
NC
TVS2
NC
TVS3
NC
TVS4
NC
K2
K9
C6
NC
LED3
LED
RLED
R4
NC
AGND
3.3V
BAT+
DCIN
BT_AVDD
DVDD
MIC
DACR-
DACL-
R/L-
DACVDD
VCOM
BAT+
3.3V
RF
DCIN
LED_B/R
CHG
PH
BAT+
DC5V
DM
DP
DM
DP
POWER
POWER
BT_OSCI
BT_OSCO
BT_OSCI BT_OSCO
$$$2
LED_B/R
DM
DP
MICBLAS
MIC
MICBLAS
MIC
DACR-
DACL-
R/L-
DACL-
R/L-
DACR-
L+
R/L
R+
L+
PH
R+
R/L
DC5V
$$$3
$$$3
$$$2
DC5V
CHG
DC5V
ADC10/SD1CMD/PC4
ADC 13/SD1CLK/PC5