TM
Arduino UNO Reference Design
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VIN IC1
3 4
IN OUT
2
+5V
U1A U1B
3 5
CMP
1 7
MC33269ST-5.0T3
2 6
+3V3
+5V
LM358D LM358D
IC2
3
VIN GND
C1 3
+5V
MC33269D-5.0
GND
100n
D1 3 2
VI VO
GATE_CMD M7
ADJ
PWRIN PC1
PC2C2
47u 100n
47u
+5V
GND GND
+5V
USBVCC
GND GND GND GND
GND
1 5
+3V3
IN OUT
+5V
3
EN C3
1u
POWER
2 4
GND NC/FB
1
RESET
2
+3V3
+5V
3
GND
GND
4
GREEN
5
ON
6 4 5
GND VIN
RN4D 1K
+5V
GND
3 6
GND
RN4C 1K
ICSP1
+5V
1 2
GND
ICSP
3 4 C4
5 6 1 2
3 4 100n
5 6
ICSP RESET-EN
+5V
1 2
U3 AREF
8
GND ICSP GND
21 7
GND
(PCINT7/OC0A/OC1C)PB7
20 6
SCK
(PCINT6)PB6
13
24 19 5
RESET2 MISO
RESET(PC1/DW) (PCINT5)PB5
F1 12
ZIC1
18 4
USBVCC MOSI
(T1/PCINT4)PB4
11
RESET
17 1 19 3
XT2 MISO2 SS
500mA (PD0/MISO/PCINT3)PB3 RESET (SCK)PB5
X2 10
2 16 18 2
MOSI2
XTAL2(PC0) (PDI/MOSI/PCINT2)PB2 (MISO)PB4
22R RN3A 9
1 8 1 15 17 1
XUSB R1 Y1 SCK2 XTAL2
(SCLK/PCINT1)PB1 Y2 (MOSI)PB3
8
2 1 14 10 16
D- RD- 1M SS
XTAL1 (SS/PCINT0)PB0 XTAL2 (SS)PB2
3 15 IOH
D+ XT1 R2 IO9
(OC1)PB1
22R RN3DRD+ 16MHz XT1R
4 5 4 1M 9 14
IO8
XTAL1 (ICP)PB0
32 22 6
XTAL1
AVCC (INT4/ICP1/CLK0)PC7
+5V AREF
23 21 28 5 2 7
GND AD5
(OC1A/PCINT8)PC6 16MHz AREF (ADC5)PC5
25 20 27 4
AD4
(PCINT9/OC1B)PC5 AVCC (ADC4)PC4 RN3B 22R
+5V
4 26 22 26 3
AD3
VCC (PCINT10)PC4 AGND (ADC3)PC3
3 5 25 2 3 6
AD2
GND (AIN2/PCINT11)PC2 (ADC2)PC2
7 24 1
UBOOT AD1
VCC (ADC1)PC1 RN3C 22R
13 1 2 8 23
AD0
(CTS/HWB/AIN6/TO/INT7)PD7 C6 GND (ADC0)PC0)
27 12
VUCAP AD
UCAP (RTS/AIN5/INT6)PD6 100n
31 11 13
USHIELD USBVCC TXLED USB boot En IO7
UVCC (XCK/AIN4/PCINT12)PD5 (AIN1)PD7
+5V
RD- 30 10 12 8
RXLED IO6
D- (INT5/AIN3)PD4 (AIN0)PD6
7
29 9 11 7
RD+ M8RXD IO5
100n D+ (TXD1/INT3)PD3 (T1)PD5
1K RN2D 6
28 8 5 4 6 6
UGND M8TXD GND IO4
C7 UGND (RXD1/AIN1/INT2)PD2 (T0)PD4
5
7 5 5
IO3
(AIN0/INT1)PD1 (INT1)PD3
TX 4
2 1 EXP 6 4 4
IO2
C8 PAD (OC0B/INT0)PD0 YELLOW (INT0)PD2
3
3 3
IO1
1u (TXD)PD1
1K RN2C 2
GROUND
6 3 2 2
GND ATMEGA8U2-MU IO0
(RXD)PD0
1
1
GND
0
ATMEGA81K RN4B
RX
7 2 IOL
YELLOW
M8RXD
M8TXD
1K RN4A
8 1
XT1 XTAL1
XT2 XTAL2
1
RN1B 10K
1
2
4
8
8
1
2
7
1
2
10K RN1A
+
+
1
T1
FDN304V
GND
L
YELLOW
TS42
RESET
RN2A
RN2B
1K
1K
1
3
2
4
5
8
1
7
2
6
3
10K RN1C
C5
100n
4
5
RN1D 10K
DTR
GND
USB
P$2
P$1
R3
27R
P$2
P$1
UGND
Z1
Z2
PGB1010604
PGB1010604
L1
BLM21
22p
22p
22p
22p
GND
GND
C11
C9
C12
C10
1
2
1
2
Q1
16MHz
Q2
16MHz