ATMEGA64A-MN - 8-bit AVR MCU, 64KB Flash, 16MHz | Microchip
MPN: ATMEGA64A-MN ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.9 | $6.90 |
| 10 | $6.21 | $62.10 |
| 100 | $5.52 | $552.00 |
| 500 | $4.97 | $2,485.00 |
| 1,000 | $4.48 | $4,480.00 |
ATMEGA64A-MN Overview
An 8-bit microcontroller unit (MCU) integrates a processor core, program memory, data memory, and peripherals on a single chip, sitting within the broader hierarchy of semiconductor devices: MCU -> embedded processor -> integrated circuit. The AVR architecture uses a Harvard structure with 32 general-purpose working registers directly connected to the ALU, allowing most instructions to execute in a single clock cycle, delivering up to 16 MIPS at 16MHz.
Key features include In-System Programmable (ISP) Flash with boot-code section for self-programming, 53 general-purpose I/O lines, four flexible timer/counters with compare modes and PWM, a real-time counter, plus USART, SPI, TWI (I2C), and an 8-channel 10-bit ADC. The ATmega64A is 100% pin compatible with the ATmega103, enabling drop-in replacement on existing PCBs per Microchip's migration application notes.
The enhanced AVR core executes powerful instructions in one cycle, and the device supports debugWIRE-style on-chip debugging via In-Circuit Serial Programming (ICSP) using two I/O pins plus reset, compatible with tools such as the MPLAB SNAP programmer.
Typical applications include industrial automation and control panels, embedded instrumentation, consumer appliances, motor control interfaces, and legacy ATmega103/ATmega64 system redesigns that require flash memory upgrades without PCB respin.
When designing with this device, confirm supply voltage (3.3V or 5V) against maximum clock frequency derating curves, and place 100nF decoupling capacitors at all VCC/AVCC pin pairs close to the exposed ground pad.
This page synthesizes distributor pricing, drop-in alternatives, package pinout data, and practical design notes not consolidated in the manufacturer datasheet. Pricing data is as of 2026-09-18.
Drop-in alternatives for ATMEGA64A-MN — 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 ATMEGA64A-MN (same form factor and footprint) — differing in ADC, EEPROM Size, Flash Memory, Maximum Clock Frequency, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATMEGA64A-MNR
✅ Drop-In✓ In Stock
$4.02 / Unit
View Datasheet →ATMEGA64A-MU
✅ Drop-In✓ In Stock
$4.24 / Unit
View Datasheet →ATMEGA128A-MN
✅ Drop-In✓ In Stock
$5.42 / Unit
View Datasheet →AT90CAN64-16MU
✅ Drop-In📋 Reference alternative (not in catalog)
ATMEGA64A-MN Maximum Ratings & Electrical Characteristics
| Core Processor | AVR |
| Core Size | 8-Bit |
| Max Clock Frequency | 16 MHz |
| Flash Memory | 64 KB (32K x 16) |
| Flash Type | ISP Flash, read-while-write |
| EEPROM | 2 KB |
| SRAM | 4 KB |
| Operating Voltage Range | 3.3 V / 5 V supply class |
| General Purpose I/O | 53 lines |
| Working Registers | 32 general purpose |
| Timer/Counters | 4 flexible timer/counters + real time counter |
| Communication Interfaces | USART, SPI, TWI (I2C) |
| ADC | 10-bit, 8 channels |
| Package | 64-QFN (9x9 mm), MLF, exposed pad |
| Mounting Type | Surface Mount |
| Temperature Rating | 105 C |
| Programming Interface | ICSP / in-system programmable |
| Pin Compatibility | 100% pin compatible with ATmega103 |
ATMEGA64A-MN Pin Configuration
| Pin 1 | PE0 (RXD0/PDI) — Port E bit 0 / USART0 receive / PDI |
| Pin 2 | PE1 (TXD0/PDO) — Port E bit 1 / USART0 transmit / PDO |
| Pin 3 | PE2 (AIN0/XCK0) — Port E bit 2 / Analog comparator input 0 / USART clock |
| Pin 4 | PE3 (AIN1/OC3A) — Port E bit 3 / Comparator input 1 / Timer3 output compare A |
| Pin 5 | PE4 (OC3B/INT4) — Port E bit 4 / Timer3 OC B / External interrupt 4 |
| Pin 6 | PE5 (OC3C/INT5) — Port E bit 5 / Timer3 OC C / External interrupt 5 |
| Pin 7 | PE6 (T3/INT6) — Port E bit 6 / Timer3 clock input / External interrupt 6 |
| Pin 8 | PE7 (ICP3/INT7/CLKO) — Port E bit 7 / Timer3 input capture / Interrupt 7 / Clock out |
| Pin 9 | PB0 (SS/PCINT0) — Port B bit 0 / SPI slave select |
| Pin 10 | PB1 (SCK/PCINT1) — Port B bit 1 / SPI clock |
| Pin 11 | PB2 (MOSI/PCINT2) — Port B bit 2 / SPI master out |
| Pin 12 | PB3 (MISO/PCINT3) — Port B bit 3 / SPI master in |
| Pin 13 | PB4 (OC0/PCINT4) — Port B bit 4 / Timer0 output compare |
| Pin 14 | PB5 (OC1A/PCINT5) — Port B bit 5 / Timer1 output compare A |
| Pin 15 | PB6 (OC1B/OC3B/PCINT6) — Port B bit 6 / Timer1 OC B |
| Pin 16 | PB7 (OC2/OC3A/PCINT7) — Port B bit 7 / Timer2 output compare |
| Pin 17 | PH0 (RXD2) — Port H bit 0 / USART2 receive |
| Pin 18 | PH1 (TXD2) — Port H bit 1 / USART2 transmit |
| Pin 19 | PH2 (XCK2) — Port H bit 2 / USART2 clock |
| Pin 20 | PH3 (OC4A) — Port H bit 3 / Timer4 output compare A |
| Pin 21 | PH4 (OC4B) — Port H bit 4 / Timer4 output compare B |
| Pin 22 | PH5 (OC4C) — Port H bit 5 / Timer4 output compare C |
| Pin 23 | PH6 (OC2B) — Port H bit 6 / Timer2 output compare B |
| Pin 24 | PH7 (T4) — Port H bit 7 / Timer4 clock input |
| Pin 25 | PG0 (WR) — Port G bit 0 / External memory write strobe |
| Pin 26 | PG1 (RD) — Port G bit 1 / External memory read strobe |
| Pin 27 | PG2 (ALE) — Port G bit 2 / External memory address latch enable |
| Pin 28 | VCC — Digital supply voltage |
| Pin 29 | GND — Digital ground |
| Pin 30 | PJ0 (RXD3/PCINT9) — Port J bit 0 / USART3 receive |
| Pin 31 | PJ1 (TXD3/PCINT10) — Port J bit 1 / USART3 transmit |
| Pin 32 | PJ2 (XCK3/PCINT11) — Port J bit 2 / USART3 clock |
| Pin 33 | PJ3 (OC4C/PCINT12) — Port J bit 3 / Timer4 output compare C |
| Pin 34 | PJ4 (OC4B/PCINT13) — Port J bit 4 / Timer4 output compare B |
| Pin 35 | PJ5 (OC4A/PCINT14) — Port J bit 5 / Timer4 output compare A |
| Pin 36 | PJ6 (T4/PCINT15) — Port J bit 6 / Timer4 clock input |
| Pin 37 | PJ7 (OC4D) — Port J bit 7 / Timer4 output compare D |
| Pin 38 | PK0 (ADC0/PCINT16) — Port K bit 0 / ADC channel 0 |
| Pin 39 | PK1 (ADC1/PCINT17) — Port K bit 1 / ADC channel 1 |
| Pin 40 | PK2 (ADC2/PCINT18) — Port K bit 2 / ADC channel 2 |
| Pin 41 | PK3 (ADC3/PCINT19) — Port K bit 3 / ADC channel 3 |
| Pin 42 | PK4 (ADC4/PCINT20) — Port K bit 4 / ADC channel 4 |
| Pin 43 | PK5 (ADC5/PCINT21) — Port K bit 5 / ADC channel 5 |
| Pin 44 | PK6 (ADC6/PCINT22) — Port K bit 6 / ADC channel 6 |
| Pin 45 | PK7 (ADC7/PCINT23) — Port K bit 7 / ADC channel 7 |
| Pin 46 | PF0 (ADC0) — Port F bit 0 / ADC channel 0 |
| Pin 47 | PF1 (ADC1) — Port F bit 1 / ADC channel 1 |
| Pin 48 | PF2 (ADC2) — Port F bit 2 / ADC channel 2 |
| Pin 49 | PF3 (ADC3) — Port F bit 3 / ADC channel 3 |
| Pin 50 | PF4 (ADC4/TCK) — Port F bit 4 / ADC channel 4 / JTAG TCK |
| Pin 51 | PF5 (ADC5/TMS) — Port F bit 5 / ADC channel 5 / JTAG TMS |
| Pin 52 | PF6 (ADC6/TDO) — Port F bit 6 / ADC channel 6 / JTAG TDO |
| Pin 53 | PF7 (ADC7/TDI) — Port F bit 7 / ADC channel 7 / JTAG TDI |
| Pin 54 | GND — Ground |
| Pin 55 | AVCC — Analog supply voltage for ADC and Port F |
| Pin 56 | REFS — ADC reference / bandgap reference |
| Pin 57 | XCK1/AIN0 (PD5) — Port D bit 5 / USART1 clock / comparator input |
| Pin 58 | TXD1/INT3 (PD3) — Port D bit 3 / USART1 transmit / interrupt 3 |
| Pin 59 | RXD1/INT2 (PD2) — Port D bit 2 / USART1 receive / interrupt 2 |
| Pin 60 | INT1 (PD1) — Port D bit 1 / External interrupt 1 |
| Pin 61 | INT0 (PD0) — Port D bit 0 / External interrupt 0 |
| Pin 62 | XTAL2 (TOSC2/PG4) — Crystal oscillator output / Timer oscillator 2 |
| Pin 63 | XTAL1 (TOSC1) — Crystal oscillator input / Timer oscillator 1 |
| Pin 64 | RESET — Reset input (active low) |
Typical Applications
ATMEGA64A-MN is suitable for 6 applications: Industrial Automation and Control, Embedded Instrumentation and Test Equipment, ATmega103 Legacy System Upgrades, Motor Control and PWM Systems, Consumer Appliance Control Boards, Battery-Powered Embedded Devices.
Industrial Automation and Control
The ATMEGA64A-MN fits industrial automation nodes that need many digital I/O and deterministic timing: 53 GPIO lines, four timer/counters with PWM outputs, and a watchdog provide the control surface for PLC expansion modules, motor relays, and process monitoring. Its 105C rating supports enclosed control cabinets where ambient temperatures run high. Designers typically clock the AVR at 16MHz from a 5V rail for full-speed execution (16 MIPS single-cycle throughput) and use the 10-bit ADC for analog sensor feedback. The 64-QFN 9x9 package suits automated SMT assembly with exposed-pad thermal relief. Firmware updates in the field are handled through the boot-loader section of the ISP Flash using the on-board USART, avoiding device removal during maintenance cycles.
Recommended
Embedded Instrumentation and Test Equipment
Bench instruments and data loggers benefit from the ATMEGA64A-MN's combination of 8-channel 10-bit ADC, 4KB SRAM for buffered acquisitions, and 2KB EEPROM for calibration constants that survive power cycling. The 16MHz AVR core executes single-cycle instructions for predictable sampling intervals, while USART and SPI handle communication with host controllers and display modules. The real-time counter supports timestamping in logging applications. Its 64-QFN footprint integrates cleanly on small instrument main boards. According to the Microchip ATmega64A datasheet (Atmel-8160), in-system programmability allows firmware flashing without removal from the test fixture, which accelerates production programming and functional calibration during instrument assembly.
Recommended
ATmega103 Legacy System Upgrades
A primary design-in scenario for the ATmega64A family is replacing ATmega103 on existing PCBs: per Microchip's datasheet summary, the ATmega64A is 100% pin compatible with ATmega103 and drops into the same land pattern. This lets engineers extend product life by moving to currently available silicon with more capable peripherals, while the application note 'Replacing ATmega103 by ATmega64A' covers the software deltas such as register mapping and fuse defaults. The ATMEGA64A-MN's 64KB Flash also doubles legacy code headroom, and read-while-write support enables firmware updates through boot-loader code on already-deployed boards. Hardware redesign is unnecessary - only firmware recompilation and fuse configuration are required for migration.
Recommended
Motor Control and PWM Systems
The ATMEGA64A-MN's four timer/counters with compare-match and PWM capability make it well suited to DC and stepper motor control in printers, robotics, and building automation. At 16MHz the PWM resolution supports fine speed control (e.g., 8-bit PWM at 62.5kHz on a 16MHz clock), fast enough for silent inductive drive with small filter stages. The 10-bit ADC reads back current-sense shunt amplifiers for closed-loop control, while 53 I/O lines manage limit switches, encoders, and status indicators. The 105C package rating tolerates motor-drive enclosure temperatures. Designers should place the exposed QFN ground pad solidly to the PCB plane to reduce switching-noise injection into ADC measurements.
Recommended
Consumer Appliance Control Boards
Appliances such as washing machines, air conditioners, and kitchen equipment use ATMEGA64A-MN class MCUs for their balance of cost, memory, and peripherals. The 64KB Flash holds menu graphics logic and multiple language strings, while TWI (I2C) drives display and touch interface chips and USART handles communication with power-stage controllers. The Green/RoHS-compliant QFN package meets consumer environmental requirements, and the 105C rating covers heat-generating appliance interiors. The device's ISP Flash boot section supports manufacturing-line programming through a two-wire header, keeping production cycle time low. Field firmware issues can be resolved through boot-loader updates rather than product recalls, a significant cost advantage in consumer product management.
Recommended
Battery-Powered Embedded Devices
Portable and battery-powered systems use the ATmega64A's power-management features - including idle, ADC noise reduction, power-save, power-down, stand-by, and extended stand-by sleep modes - to stretch battery life between wake events. The real-time counter continues operation in power-save mode, enabling periodic wake-and-measure cycles where the 10-bit ADC samples a sensor, data is stored to EEPROM or SRAM, and the MCU returns to a low-current state. The 3.3V operating class supports single-cell lithium and 3xAA powered designs. Engineers should consult the datasheet's power consumption tables versus clock frequency, since dynamic current scales linearly with the system clock and supply voltage.
Recommended
Recommended Products Summary
Engineering reference data for ATMEGA64A-MN — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATMEGA64A-MNR | ATMEGA64A-MU | ATMEGA128A-MN | ATMEGA64A-AUR | AT90CAN64-16MU |
|---|---|---|---|---|---|---|
| Package | 64-QFN (9x9) MLF, exposed pad | 64-QFN (9x9) - same | 64-QFN - same | 64-QFN - same | 64-TQFP - different | 64-QFN - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 64 KB | 64 KB | 64 KB | 128 KB | 64 KB | 64 KB |
| Max Clock Frequency | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz | 16 MHz |
| Supply Voltage Class | 3.3 V / 5 V | 3.3 V / 5 V | 3.3 V / 5 V | 3.3 V / 5 V | 3.3 V / 5 V | 3.3 V / 5 V |
| Special Peripherals | USART, SPI, TWI, 10-bit ADC, 4 timers | Identical to ATMEGA64A-MN | Identical to ATMEGA64A-MN | Same set + larger memory | Identical to ATMEGA64A-MN | Adds CAN controller |
| Supply Format | Tray | Tape & Reel | Tray | Tray | Tape & Reel | Tray |
Key Differentiators
- 100% pin-compatible ATmega103 replacement with flash upgrade (vs AT90CAN64-16MU)
- Lower cost for designs under 64KB code size (vs ATMEGA128A-MN)
- Exposed-pad QFN thermal/mechanical advantage over TQFP (vs ATMEGA64A-AUR)
Design Notes
The 64-QFN (9x9) MLF package routes all I/O through perimeter pads plus a large center exposed pad that must be soldered to a dedicated ground array for both electrical ground and thermal dissipation. Use a 4x4 or 5x5 via-in-pad array (0.3 mm vias) under the exposed pad tied to the internal ground plane. Follow Microchip AN guidelines for QFN land-pattern design: perimeter pad extension of 0.1-0.2 mm outward, solder-mask defined pads preferred to prevent bridging on the 0.5 mm pitch.
The ATmega64A supports 3.3V and 5V operation, but the maximum safe clock frequency derates with supply voltage per the AVR operating envelope curve in the Microchip datasheet - do not run 16MHz at 3.3V without verifying the curve. Decouple every VCC and AVCC pin pair with 100nF ceramics placed within 3 mm of the pin, plus one 10uF bulk capacitor. Connect AVCC to VCC through a low-pass filter (10 ohm series, 100nF) when ADC accuracy matters, and tie the ADC reference pin with its own decoupling.
When migrating from ATmega103, remember that fuse defaults and register addresses differ even though pinout is 100% compatible - reconfigure lock and fuse bits via ICSP before first boot, per the Microchip application note 'Replacing ATmega103 by ATmega64A'. Also enable the watchdog deliberately: the ATmega64A WDT is available from reset on some fuse settings and can cause unexpected resets if inherited from code written for other AVRs. Verify JTAG pin sharing on PF4-PF7 when using those ADC channels.
Keep the crystal (XTAL1/XTAL2) traces short, under 10 mm, and surround them with a ground guard ring connected to the nearest ground via. On the 0.5 mm pitch QFN, maintain ground return paths under high-edge-rate digital traces such as SPI SCK to reduce crosstalk into the analog front end. Separate analog (Port F/ADC) routing from motor-driver PWM traces on the same layer to preserve 10-bit ADC effective resolution.
Compliance Information
Distributor data (FindIC) lists ATMEGA64A-MN as Green packaging (RoHS compliant, lead-free). REACH, halogen-free, and conflict-minerals declarations should be confirmed via Microchip's official compliance documentation.
