Arduino UNO R3 User Manual

Arduino® UNO R3
2 / 13 Arduino® UNO R3 / Rev. 01 - 25/11/2021
Features
ATMega328P Processor
Memory
AVR CPU at up to 16 MHz
32KB Flash
2KB SRAM
1KB EEPROM
Security
Power On Reset (POR)
Brown Out Detection (BOD)
Peripherals
2x 8-bit Timer/Counter with a dedicated period register and compare channels
1x 16-bit Timer/Counter with a dedicated period register, input capture and compare channels
1x USART with fractional baud rate generator and start-of-frame detection
1x controller/peripheral Serial Peripheral Interface (SPI)
1x Dual mode controller/peripheral I2C
1x Analog Comparator (AC) with a scalable reference input
Watchdog Timer with separate on-chip oscillator
Six PWM channels
Interrupt and wake-up on pin change
ATMega16U2 Processor
8-bit AVR® RISC-based microcontroller
Memory
16 KB ISP Flash
512B EEPROM
512B SRAM
debugWIRE interface for on-chip debugging and programming
Power
2.7-5.5 volts

Arduino UNO R3 Specifications

General

Microcontroller	ATmega328P
Operating Voltage	5V
Input Voltage (recommended)	7-12V
Input Voltage (limit)	6-20V
Digital I/O Pins	14 (of which 6 provide PWM output)
PWM Digital I/O Pins	6
Analog Input Pins	6
DC Current per I/O Pin	20 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	32 KB (ATmega328P) of which 0.5 KB used by bootloader
SRAM	2 KB (ATmega328P)
EEPROM	1 KB (ATmega328P)
Clock Speed	16 MHz
LED_BUILTIN	13
Length	68.6 mm
Width	53.4 mm
Weight	25 g