Pinout
Arduino Nano (ATmega328P) pinout
Pins
- 1: D1 — TX
- 2: D0 — RX
- 3: RESET
- 4: GND
- 5: D2
- 6: ~D3
- 7: D4
- 8: ~D5
- 9: ~D6
- 10: D7
- 11: D8
- 12: ~D9
- 13: ~D10 — SS
- 14: ~D11 — COPI
- 15: D12 — CIPO
- 30: VIN
- 29: GND
- 28: RESET
- 27: +5V
- 26: A7
- 25: A6
- 24: A5 — SCL
- 23: A4 — SDA
- 22: A3
- 21: A2
- 20: A1
- 19: A0
- 18: AREF
- 17: 3V3
- 16: D13 — SCK
Specifications
| Microcontroller | ATmega328P |
|---|---|
| Operating voltage | 5 V |
| Input voltage (VIN) | 7–12 V |
| Digital I/O pins | 14 (6 PWM) |
| Analog input pins | 8 (A6, A7 analog only) |
| DC current per I/O pin | 20 mA (40 mA absolute max) |
| Flash memory | 32 KB, of which 2 KB used by bootloader |
| SRAM | 2 KB |
| EEPROM | 1 KB |
| Clock speed | 16 MHz |
| USB | Mini-B, FT232RL (clones: CH340) |
| Size | 18 × 45 mm |
Notes
- Same ATmega328P as the Uno: 40mA absolute maximum per I/O pin, 200mA total across VCC/GND combined.
- 3.3V comes from its own small onboard regulator, not the 5V rail — budget it the same way as the Uno’s 3.3V pin: fine for a sensor, not a motor or an LED strip.
