What is the operating logic voltage of Arduino Mega 2560 Rev3?

Arduino Mega 2560 Rev3 operates at a 5.0 V logic level. Connecting higher voltage signals requires a voltage divider or logic-level shifter unless 5V tolerance is explicitly specified.

What microcontroller (MCU) powers Arduino Mega 2560 Rev3?

Arduino Mega 2560 Rev3 is powered by the ATmega2560 (8-bit AVR RISC).

How many pins does Arduino Mega 2560 Rev3 have?

Arduino Mega 2560 Rev3 features 92 physical pins across its connector headers.

Embedded hardware reference for engineers and makers

Arduino Mega 2560 Rev3 Pinout & Hardware Architecture

92-pin interactive pinout

Arduino Mega 2560 Rev3 is the flagship 8-bit development platform featuring the Microchip ATmega2560 microcontroller (16 MHz, 256 KB Flash, 8 KB SRAM). Designed for complex 3D printing (RAMPS), robotics, and multi-sensor automation projects.

Arduino
Verified source
Updated Sep 2026

GPIO
Power
Ground
Analog
Control
Bus
Not connected

Tap a row of pins to see it up close

BOARD SUMMARY

ATmega2560

Arduino Mega 2560 Rev3

ATmega2560

Arduino

MCU: ATmega2560
CPU core: 8-bit AVR RISC
Clock speed: 16 MHz
SRAM: 8 KB
Flash: 256 KB
GPIO count: 72
Logic voltage: 5.0 V
Form factor: 92-pin, USB-to-Serial (ATmega16U2)

Before you wire

5 V logic — level-shift 3.3 V peripherals

Check your SPI connections: Do not use pins 10-13 for hardware SPI; connect to pins D50-D53 or the 6-pin ICSP header.
Verify peripheral voltage compatibility: 3.3V devices require logic level converters.
Do not overload the 3.3V rail (maximum 50 mA from the LP2985 linear regulator).

QUICK LINKS

Pin table

Showing 92 of 92 pins

Arduino Mega 2560 Rev3 pin table: physical pin, name, GPIO, functions, ADC, touch, default role, flags
Pin	Name	GPIO	Functions	ADC	Default role
1 power	NC	—	nc	—	No Connection
2 power	IOREF	—	power	—	Power Supply
3 power	RESET	—	reset	—	Reset / Enable
4 power	3V3	—	power	—	Power Supply
5 power	5V	—	power	—	Power Supply
6 power	GND	—	gnd	—	Ground
7 power	GND	—	gnd	—	Ground
8 power	VIN	—	power	—	Power Supply
1 adcl	A0	GPIO54	gpioadc	—	GPIO
2 adcl	A1	GPIO55	gpioadc	—	GPIO
3 adcl	A2	GPIO56	gpioadc	—	GPIO
4 adcl	A3	GPIO57	gpioadc	—	GPIO
5 adcl	A4	GPIO58	gpioadcjtag	—	GPIO
6 adcl	A5	GPIO59	gpioadcjtag	—	GPIO
7 adcl	A6	GPIO60	gpioadcjtag	—	GPIO
8 adcl	A7	GPIO61	gpioadcjtag	—	GPIO
1 adch	A8	GPIO62	gpioadc	—	GPIO
2 adch	A9	GPIO63	gpioadc	—	GPIO
3 adch	A10	GPIO64	gpioadc	—	GPIO
4 adch	A11	GPIO65	gpioadc	—	GPIO
5 adch	A12	GPIO66	gpioadc	—	GPIO
6 adch	A13	GPIO67	gpioadc	—	GPIO
7 adch	A14	GPIO68	gpioadc	—	GPIO
8 adch	A15	GPIO69	gpioadc	—	GPIO
1 digital_high	SCL	GPIO21	i2c	—	GPIO
2 digital_high	SDA	GPIO20	i2c	—	GPIO
3 digital_high	AREF	—	input	—	GPIO
4 digital_high	GND	—	gnd	—	Ground
5 digital_high	13	GPIO13	gpiospipwmled	—	GPIO
6 digital_high	12	GPIO12	gpiopwm	—	GPIO
7 digital_high	11	GPIO11	gpiopwm	—	GPIO
8 digital_high	10	GPIO10	gpiopwm	—	GPIO
9 digital_high	9	GPIO9	gpiopwm	—	GPIO
10 digital_high	8	GPIO8	gpiopwm	—	GPIO
1 digital_low	7	GPIO7	gpiopwm	—	GPIO
2 digital_low	6	GPIO6	gpiopwm	—	GPIO
3 digital_low	5	GPIO5	gpiopwm	—	GPIO
4 digital_low	4	GPIO4	gpiopwm	—	GPIO
5 digital_low	3	GPIO3	gpiopwminput	—	GPIO
6 digital_low	2	GPIO2	gpiopwminput	—	GPIO
7 digital_low	1	GPIO1	gpiouart	—	GPIO
8 digital_low	0	GPIO0	gpiouart	—	GPIO
1 communication	14	GPIO14	gpiouart	—	GPIO
2 communication	15	GPIO15	gpiouart	—	GPIO
3 communication	16	GPIO16	gpiouart	—	GPIO
4 communication	17	GPIO17	gpiouart	—	GPIO
5 communication	18	GPIO18	gpiouartinput	—	GPIO
6 communication	19	GPIO19	gpiouartinput	—	GPIO
7 communication	20	GPIO20	gpioi2cinput	—	GPIO
8 communication	21	GPIO21	gpioi2cinput	—	GPIO
1 digital_double	5V	—	power	—	Power Supply
2 digital_double	5V	—	power	—	Power Supply
3 digital_double	22	GPIO22	gpio	—	GPIO
4 digital_double	23	GPIO23	gpio	—	GPIO
5 digital_double	24	GPIO24	gpio	—	GPIO
6 digital_double	25	GPIO25	gpio	—	GPIO
7 digital_double	26	GPIO26	gpio	—	GPIO
8 digital_double	27	GPIO27	gpio	—	GPIO
9 digital_double	28	GPIO28	gpio	—	GPIO
10 digital_double	29	GPIO29	gpio	—	GPIO
11 digital_double	30	GPIO30	gpio	—	GPIO
12 digital_double	31	GPIO31	gpio	—	GPIO
13 digital_double	32	GPIO32	gpio	—	GPIO
14 digital_double	33	GPIO33	gpio	—	GPIO
15 digital_double	34	GPIO34	gpio	—	GPIO
16 digital_double	35	GPIO35	gpio	—	GPIO
17 digital_double	36	GPIO36	gpio	—	GPIO
18 digital_double	37	GPIO37	gpio	—	GPIO
19 digital_double	38	GPIO38	gpio	—	GPIO
20 digital_double	39	GPIO39	gpio	—	GPIO
21 digital_double	40	GPIO40	gpio	—	GPIO
22 digital_double	41	GPIO41	gpio	—	GPIO
23 digital_double	42	GPIO42	gpio	—	GPIO
24 digital_double	43	GPIO43	gpio	—	GPIO
25 digital_double	44	GPIO44	gpiopwm	—	GPIO
26 digital_double	45	GPIO45	gpiopwm	—	GPIO
27 digital_double	46	GPIO46	gpiopwm	—	GPIO
28 digital_double	47	GPIO47	gpio	—	GPIO
29 digital_double	48	GPIO48	gpio	—	GPIO
30 digital_double	49	GPIO49	gpio	—	GPIO
31 digital_double	50	GPIO50	gpiospi	—	GPIO
32 digital_double	51	GPIO51	gpiospi	—	GPIO
33 digital_double	52	GPIO52	gpiospi	—	GPIO
34 digital_double	53	GPIO53	gpiospi	—	GPIO
35 digital_double	GND	—	gnd	—	Ground
36 digital_double	GND	—	gnd	—	Ground
1 icsp	MISO	—	spi	—	GPIO
2 icsp	5V	—	power	—	Power Supply
3 icsp	SCK	—	spi	—	GPIO
4 icsp	MOSI	—	spi	—	GPIO
5 icsp	RESET	—	reset	—	Reset / Enable
6 icsp	GND	—	gnd	—	Ground

Grounded reference

Board overview

Arduino Mega 2560 Rev3 is a full-sized development board based on the ATmega2560 microcontroller. It features 54 digital input/output pins, 16 analog inputs, 4 hardware serial ports, a 16 MHz quartz crystal, a USB Type-B port, a 2.1mm DC power jack, and a reset button.

Power inputs

USB Type-B connector (5V DC, protected by a 500 mA resettable Polyswitch PTC)
VIN pin or 2.1mm center-positive barrel jack (7–12V DC recommended, 6–20V absolute limits)
Regulated 5.0V system power rail (NCP1117 / LD1117 linear regulator, up to 800 mA when powered via DC jack)

Common use cases

Driving 3D printers and CNC machines using RAMPS 1.4 / 1.6 shield architectures.
Complex robotics requiring dozens of simultaneous servo outputs and motor controllers.
Multi-sensor monitoring (16 ADC channels) and multi-bus telemetry across 4 independent UART channels.

Notes

SPI Bus Relocation: On Arduino Mega, hardware SPI is routed to pins D50 (MISO), D51 (MOSI), D52 (SCK), D53 (SS) and the central ICSP header. Shields relying on pins 11-13 of the Uno require connection via the ICSP header.
Native 5.0V TTL Logic: All I/O pins operate at 5V. 3.3V sensors require bidirectional level translators.
Recommended DC current per pin is 20 mA (40 mA maximum). Total microcontroller package current must not exceed 200 mA.
15 PWM channels driven by hardware Timers 0, 1, 2, 3, 4, and 5 (D2–D13, D44–D46).

Before you wire

Check your SPI connections: Do not use pins 10-13 for hardware SPI; connect to pins D50-D53 or the 6-pin ICSP header.
Verify peripheral voltage compatibility: 3.3V devices require logic level converters.
Do not overload the 3.3V rail (maximum 50 mA from the LP2985 linear regulator).

Specifications

MCU: ATmega2560
CPU core: 8-bit AVR RISC
Clock: 16 MHz
SRAM: 8 KB
Flash: 0.25 MB
GPIO count: 72
Logic voltage: 5.0 V
Operating voltage (VIN): 7 - 12 V

Primary sources

Arduino Mega 2560 Rev3 Official Schematic Arduino Mega 2560 Rev3 Eagle CAD Reference Design ATmega640/1280/1281/2560/2561 8-bit AVR Microcontroller Datasheet

Safe GPIO pins

All digital and analog pins operate on native 5.0V logic with a continuous rating of up to 20 mA per pin (absolute maximum 40 mA). Total microcontroller package current is limited to 200 mA.

ADC and analog pins

16 analog channels (A0–A15, 10-bit resolution from 0 to 5V or external AREF). Channels A4–A7 are multiplexed with the hardware JTAG interface (TCK, TMS, TDO, TDI).

I2C, SPI and UART pins

4 hardware UART ports: Serial0 (D0/D1), Serial1 (D19/D18), Serial2 (D17/D16), Serial3 (D15/D14). Hardware SPI bus on pins D50 (MISO), D51 (MOSI), D52 (SCK), D53 (SS), and the central 2x3 ICSP header (NOT on pins 10-13!). Hardware I2C on D20 (SDA) and D21 (SCL).

Strapping and boot pins

No strapping pins present. Pin D13 is connected to yellow user LED 'L' via an LMV358 op-amp buffer. D0/D1 are shared with the ATmega16U2 USB-to-serial bridge.

Input-only pins

All 54 digital pins support bidirectional I/O with internal pull-up resistors (20–50 kΩ). 15 pins provide hardware 8/16-bit PWM (D2–D13, D44–D46). 6 pins feature external hardware interrupts (D2, D3, D18, D19, D20, D21).

Arduino Pro Mini pinout NodeMCU v2 Amica (ESP8266) pinout Raspberry Pi 40-Pin GPIO Header pinout Raspberry Pi Pico pinout

Help keep this page accurate

Checked this pinout against your board or connector? Confirm it, or report a pin, voltage or orientation that does not match.

Report a problem Confirm this pinout

Opens a public form on GitHub with this page already filled in; a free GitHub account is needed. How reports and confirmations work

5 V logic — level-shift 3.3 V peripherals

QUICK LINKS

Pin table

Board overview

Power inputs

Common use cases

Notes

Before you wire

Specifications

Primary sources

Safe GPIO pins

ADC and analog pins

I2C, SPI and UART pins

Strapping and boot pins

Input-only pins

Related board pinouts

Help keep this page accurate