ATMEGA2560-16AU - 8-bit AVR MCU 256KB Flash 16MHz | Microchip
MPN: ATMEGA2560-16AU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $11.21 | $11.21 |
| 10 | $10.65 | $106.50 |
| 100 | $9.98 | $998.00 |
| 500 | $9.42 | $4,710.00 |
| 1,000 | $8.87 | $8,870.00 |
ATMEGA2560-16AU Overview
A microcontroller unit (MCU) is a single integrated circuit that combines a processor core, memory, and programmable peripherals into one chip, forming the lowest tier of the embedded computing hierarchy (MCU -> embedded processor -> system-on-chip -> computing system). The ATmega2560 belongs to the AVR family of enhanced RISC microcontrollers, executing most instructions in a single clock cycle to achieve throughput approaching 1 MIPS per MHz, allowing designers to optimize power consumption versus processing speed.
Key features include 256 KB of in-system programmable Flash with a separate boot sector supporting In-Application Programming, 4 KB EEPROM for non-volatile parameter storage, 8 KB internal SRAM, and 86 GPIO lines with internal pull-ups. The peripheral set comprises six flexible timer/counters with compare modes, four 8-bit PWM channels, six/two 16-bit PWM channels, an 8-channel 10-bit ADC, four USARTs, SPI, TWI (I2C), and a JTAG interface for on-chip debugging and boundary scan.
The AVR core uses a Harvard architecture with 32 general-purpose working registers directly connected to the ALU, so two independent registers can be accessed in one instruction executed in one cycle. This RISC structure delivers code efficiency and deterministic execution suited to real-time control tasks, while the rich peripheral bank offloads timing-critical functions from software.
Typical applications include the Arduino Mega 2560 development platform, industrial automation controllers, robotics and motor control systems, and instrumentation requiring many I/O channels and multiple serial links. Four hardware USARTs and the 86 I/O lines make it especially popular for boards that must drive shields, displays, and sensors simultaneously.
When designing with the ATMEGA2560-16AU, remember it is rated for 4.5V to 5.5V operation at 16 MHz; lower-speed grades (the V variant) run at reduced voltage, so check supply rail compatibility before substituting. Provide 100 nF decoupling on each VCC pin pair and route the analog AVCC supply cleanly for best ADC accuracy.
This page synthesizes distributor pricing, drop-in alternatives, pinout guidance, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATMEGA2560-16AU β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ATMEGA2560-16AU (same form factor and footprint) β differing in Package, ADC Channels, Instructions, Supply Voltage Range, Timers/Counters.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATMEGA1280-16AU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA640-16AU
β Drop-Inπ Reference alternative (not in catalog)
ATMEGA2560V-8AU
β Drop-Inβ In Stock
$11.3 / Unit
View Datasheet βATMEGA2560-16AU Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit AVR RISC |
| Core Size | 8-bit |
| Max Clock Frequency | 16 MHz |
| Program Memory Type | FLASH (ISP) |
| Flash Memory Size | 256 KB (128K x 16) |
| SRAM Size | 8 KB |
| EEPROM Size | 4 KB |
| Number of I/O Lines | 86 |
| Working Registers | 32 general purpose |
| Supply Voltage (VCC) | 4.5 V to 5.5 V (at 16 MHz) |
| ADC Resolution | 10 bit |
| ADC Channels | 8 (16 with ADC mux on PK port) |
| Number of USARTs | 4 |
| Timers/Counters | 6 (flexible, with compare and PWM modes) |
| Interface Types | SPI, TWI (I2C), JTAG, USART |
| Package | 100-TQFP (14x14 mm) |
| Mounting Type | Surface Mount |
| MIPS | Up to 16 MIPS (approx. 1 MIPS per MHz) |
ATMEGA2560-16AU 100-tqfp (14x14 mm) Pin Configuration Guide
Pin configuration for ATMEGA2560-16AU (100-tqfp (14x14 mm) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for ATMEGA2560-16AU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATMEGA2560-16AU is suitable for 6 applications: Arduino Mega 2560 Platform, Industrial Automation Control, Robotics and Motor Control, Instrumentation and Data Logging, Building Automation and Smart Home Hubs, Prototyping and Education.
Arduino Mega 2560 Platform
The ATMEGA2560-16AU is the official core processor of the Arduino Mega 2560 and its R3 revisions. Its 256 KB Flash hosts the Arduino bootloader plus large user sketches, while 86 GPIO lines map directly to the Mega's 54 digital and 16 analog headers, allowing multiple stacked shields to operate simultaneously. Four hardware USARTs serve USB-serial bridging and external serial devices without software emulation overhead. Its 16 MHz clock yields roughly 16 MIPS, adequate for typical Arduino workloads, and its 5V logic matches the vast ecosystem of legacy Arduino shields that never migrated to 3.3V platforms.
Recommended
Industrial Automation Control
In factory automation panels, the ATMEGA2560-16AU's 86 I/O lines replace external port expanders, reducing BOM cost and failure points in relay- and sensor-heavy control logic. The six timers generate precise PWM for actuators and provide input capture for sensor pulse timing, while the four USARTs interface Modbus RTU slaves, HMI panels, and barcode readers concurrently. Its 5V noise margin suits electrically harsh cabinets better than 3.3V MCUs, and the 10-bit ADC handles analog transducer inputs with adequate resolution for monitoring. The JTAG interface supports on-chip debugging during commissioning of machine-control firmware.
Recommended
Robotics and Motor Control
Robot controllers benefit from the ATMEGA2560-16AU's multiple 16-bit timers, which drive up to dozens of servo channels with hardware-scheduled pulses, freeing CPU cycles for navigation algorithms. Sixteen analog input channels monitor battery voltage, current sense resistors, and potentiometer feedback, while four USARTs connect motor drivers, IMUs, and telemetry radios in parallel. The 8 KB SRAM accommodates kinematics buffers and sensor fusion state that overflow smaller AVRs. The Mega footprint's popularity in robotics (line-followers, hexapods, 3D printer mainboards) means extensive community code and shield hardware already target this exact MCU.
Recommended
Instrumentation and Data Logging
Test and measurement fixtures use the ATMEGA2560-16AU as a sequencer and data aggregator: its 10-bit ADC with 16 muxed channels samples up to 16 sensor points, EEPROM (4 KB) stores calibration constants that survive power cycles, and 256 KB Flash holds firmware plus buffered lookup tables. Four USARTs stream results to a host PC, a thermal printer, and a display controller simultaneously. The TWI (I2C) bus adds external EEPROM or RTC expansion. Its deterministic single-cycle RISC execution gives repeatable sample timing, which matters for logging intervals and PWM stimulus generation in bench fixtures.
Recommended
Building Automation and Smart Home Hubs
Custom home-automation controllers employ the ATMEGA2560-16AU where many wired points are needed: 86 GPIO lines handle zone switches, relays, and LED indicators directly, while the TWI bus addresses environmental sensor clusters. The 5V supply tolerance simplifies integration with legacy alarm-panel signaling that does not conform to 3.3V logic levels. Its 256 KB Flash supports substantial protocol stacks such as MQTT-over-serial or X10 implementations with room for OTA-style bootloaders, and the 8 KB SRAM holds multiple socket buffers. Four USARTs allow simultaneous RS-485, RS-232, and wireless module interfaces in one node.
Recommended
Prototyping and Education
Engineering education and rapid prototyping platforms standardize on the ATMEGA2560-16AU because the Arduino Mega ecosystem provides mature toolchains, bootloaders, and libraries that remove initial tooling friction. Students wire directly to the 5V-tolerant 86 I/O lines without level shifters, and the generous Flash (256 KB) means complex course projects never hit memory limits. In professional prototyping, the same part lets teams validate control logic on a Mega board before committing to a custom PCB, since the TQFP footprint carries directly from dev board to production layout with identical firmware and JTAG debugging flow.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA2560-16AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA1280-16AU | ATMEGA640-16AU | ATMEGA2560V-8AU |
|---|---|---|---|---|
| Package | 100-TQFP (14x14 mm) | 100-TQFP (14x14 mm) - same | 100-TQFP (14x14 mm) - same | 100-TQFP (14x14 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 256 KB | 128 KB | 64 KB | 256 KB |
| SRAM | 8 KB | 8 KB | 8 KB | 8 KB |
| EEPROM | 4 KB | 4 KB | 4 KB | 4 KB |
| Max Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 8 MHz |
| GPIO Lines | 86 | 86 | 86 | 86 |
| Supply Voltage | 4.5 V to 5.5 V (at 16 MHz) | 4.5 V to 5.5 V (at 16 MHz) | 4.5 V to 5.5 V (at 16 MHz) | 1.8 V to 5.5 V (at 8 MHz) |
Key Differentiators
- Largest Flash in the pin-compatible family (vs ATMEGA1280-16AU)
- Full 16 MHz throughput on a 5V rail (vs ATMEGA2560V-8AU)
- Memory-optimized cost path exists without redesign (vs ATMEGA640-16AU)
Design Notes
Provide a 100 nF ceramic decoupling capacitor at every VCC/GND pin pair of the 100-TQFP package - there are multiple power pin pairs distributed around the 14x14 mm body, and missing even one degrades high-speed output edge quality. Place capacitors within 2 mm of the pins on the bottom layer with short vias to the ground plane. The exposed perimeter also carries AVCC and AREF: isolate the analog supply with an RC filter (ferrite bead plus 100 nF) from the digital 5V rail to preserve ADC accuracy on the 16 analog channels.
The -16AU speed grade requires a regulated 4.5V-5.5V supply; do not power it from an unregulated or 3.3V rail. Estimated: at 16 MHz with typical peripheral loading, supply current is in the tens of milliamps range - size the 5V regulator for the MCU plus all loads driven by the 86 GPIO lines, which can dominate total current. If the system rail is 3.3V, use the ATMEGA2560V-8AU instead (1.8V-5.5V, 8 MHz max) rather than level-shifting or overclocking the 16AU out of specification.
Do not exceed 16 MHz on the -16 grade and observe the documented frequency-versus-voltage operating envelope from the Microchip datasheet. On Mega 2560-compatible board repairs, remember a replacement chip ships blank: flash the Arduino bootloader via the ICSP header before expecting USB sketch upload. Also reserve the four JTAG pins (TCK/TMS/TDO/TDI) appropriately - JTAG is enabled by default and those pins are unavailable as GPIO unless the JTAGEN fuse is cleared, a frequent source of 'missing I/O pins' confusion on this device.
Compliance Information
Compliance status not stated in the provided web data; verify RoHS/REACH status on the Microchip product page or distributor environmental data before final sourcing.
