Schematics

1
1
2
2
3
3 4
D D
C C
B B
A A
PE7/ADC9
1
AGND
2
PE0
3
VUSB
4
VDDIO
5
VBAT
6
DGND
7
VDDBT
8
PWRKEY
9
BT ANT
10
BT OSCI
11
BT OSCO
12
ADC5/PB3
13
ADC10/MICL/PF2
14
DACR
15
DACL
16
U1
AB5337A
12
BT-ANT1
ANTENNA_PIFA
GND
R1 0R
BT RF
PWRKEY
BT-OSCI
BT-OSCO
Y1
26MHZ
DACL
GND
VDDIO
VDDBT
MUTE
GND
C8 105
C7 105
C6 104
GND
VBUS
1
D-
2
D+
3
GND
4
G
5
G
6
G
7
G
8
G
9
USB1
USB-MICRO
VUSB
BT1
3.4V~4.2V
C11
105
VBAT
R7
3K6
CHRG
1
GND
2
BAT
3
VCC
4
PROG
5
U3
4054
CHARGE
R9
1K
LED00
LED2
0603/
GND
S1
VMCU
LOUL-
LOUL+
C5
473
R2 10K
GND
C3 105
MUTE
C10
106
GND
DACL
VMCU
1
2
J1 SPK
R3
30K
GND
SD
1
BYP
2
MODE
3
IN
4
VON
5
VDD
6
GND
7
VOP
8
GND
9
U2
5128
LOUL+
LOUL-
LED1
Blue 0603
LED01
R6
100K
VMCU
C4 472
GND
GND
PWRKEY
R12 100K
LED01
Blue
Red