Schematic

ICSP
+5V
GND
10k
+5V
+5V
GND
16MHz
GND
100u
GND
GND
+5V
100u
GND
+3V3
2k2
2k2
GND
1K
+3V3
MAX1676
ATMEGA328P-AU
GND
GND
GND
100n
GND
+5V
GND
100k
1K
BATT-LOW
180
100k
0
GND
GND
+3V3
100n
22p22p
100n
GND
1K
100n
GND
100n
GND
MC33269D-3.3
100u
GND
GND
+5V
1 2
3 4
5 6
ICSP
R1
21
Q1
1
2
3
4
5
6
7
8
J1
1
2
3
4
5
6
7
8
J3
1
2
3
4
5
6
J2
C7
3 1
24
S1
D1
C13
R2
R3
3V3
R4
SHDN/
6
LBI
2
LBO/
3
REF
5
FB
1
LX
9
OUT
10
GND
8
IC5
BATT
7
CSEL
4
PB5(SCK)
17
PB7(XTAL2/TOSC2)
8
PB6(XTAL1/TOSC1)
7
GND
3
GND
5
VCC
4
VCC
6
AGND
21
AREF
20
AVCC
18
PB4(MISO)
16
PB3(MOSI/OC2)
15
PB2(SS/OC1B)
14
PB1(OC1A)
13
PB0(ICP)
12
PD7(AIN1)
11
PD6(AIN0)
10
PD5(T1)
9
PD4(XCK/T0)
2
PD3(INT1)
1
PD2(INT0)
32
PD1(TXD)
31
PD0(RXD)
30
ADC7
22
ADC6
19
PC5(ADC5/SCL)
28
PC4(ADC4/SDA)
27
PC3(ADC3)
26
PC2(ADC2)
25
PC1(ADC1)
24
PC0(ADC0)
23
PC6(/RESET)
29
IC1
C5
L1
1
X1-1
2
X1-2
R11
R12
BATT-LOW
R13
R14
R15
GND
1
3V3
2
PIO2
3
PIO3
4
NRTS
5
RXD
6
PCMO
7
USB_D+
8
USB_D-
9
NCTS
10
PCMI
11
PCMC
12
PCMS
13
GND
14
GND
15
3V3
16
RES
17
PIO6
18
PIO7
19
PIO4
20
NCSB
21
SCLK
22
MISO
23
MOSI
24
PIO5
25
TXD
26
AIO
27
GND
28
C1
C2C3
C4
R6
C8
1
2
3
4
5
6
7
8
9
10
SV1
1
2
3
4
5
6
7
8
9
10
SV2
21
SJ1
C9
1
JP1
2
VI
3
1
VO
2
IC2
ADJ
1
JP2
2
21
SJ3
C6
1
2
3
4
POWER
+5V
+5V
+5V
+5V
GND
AREF
AREF
RESET
VIN
VIN
SCK
MOSI
XTAL2
XTAL1
SS
INT
WOL
+3V3
TX
TX
RX
RX
N$27
N$28
N$29
N$24
BT_RES
N$4
BTRES
MISO
N$10
+
+
IC3
WT11
+
OSEPP Bluetooth (Arduino Compatible)
OSEPP-BTH-01 (Rev1.1)
Based on Arduino Bluetooth Design