ATXMEGA64A3-MH - 32MHz 64KB AVR Microcontroller | Microchip
MPN: ATXMEGA64A3-MH ✓ ActiveATXMEGA64A3-MH Overview
An AVR XMEGA microcontroller is an embedded semiconductor that combines a processor core, program and data memory, communication peripherals, timers, and event-management hardware in one device. The XMEGA A3 family sits within the broader hierarchy of 8/16-bit AVR microcontrollers, embedded controllers, and microcontrollers used for low-power control and signal-processing applications.
The ATXMEGA64A3-MH includes 64 KB of Flash organized as 32K x 16, a separate 4 KB boot-code section, 4 KB SRAM, and 2 KB EEPROM. Its four-channel DMA controller and eight-channel event system allow data movement and event routing between peripherals without requiring every transfer to be handled directly by the CPU.
At a maximum clock of 32 MHz, the device delivers up to 32 MIPS throughput. This processing capability, together with the 16-bit Flash organization and event-system architecture, supports responsive control loops and coordinated peripheral operations while maintaining the low-power characteristics associated with the AVR XMEGA family.
Typical uses include industrial control, sensor acquisition, communication modules, low-power embedded systems, and compact control platforms. The 1.6 V to 3.6 V operating range makes the device suitable for low-voltage embedded systems, while 64 KB of Flash provides room for firmware, configuration data, and a boot section within one microcontroller.
Designers should verify the complete 64-pin pinout, exposed-pad connection, clock configuration, decoupling requirements, and peripheral assignments against the manufacturer datasheet before layout. The 64-QFN footprint also requires careful thermal-via placement and PCB-land-pattern verification to maintain reliable heat transfer from the exposed pad.
This page consolidates verified manufacturer and distributor information, separates the exact ATXMEGA64A3-MH characteristics from related family variants, and identifies which drop-in alternatives require firmware or peripheral review before substitution.
Drop-in alternatives for ATXMEGA64A3-MH — 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 ATXMEGA64A3-MH (same form factor and footprint) — differing in Package, Family, Maximum CPU Speed, Operating Temperature, RoHS Status.
ATXMEGA64A3U-MH
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ATXMEGA64A4-MH
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ATXMEGA128A3-MH
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ATXMEGA128A4-MH
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ATXMEGA64A4U-MH
✅ Drop-In ⚠️ Specs UnverifiedContact for price
View Datasheet →ATXMEGA64A3-MH Maximum Ratings & Electrical Characteristics
| Controller Type | AVR XMEGA A3 8/16-bit microcontroller |
| Maximum Clock Frequency | 32 MHz |
| Maximum Throughput | Up to 32 MIPS at 32 MHz |
| Program Memory | 64 KB Flash (32K x 16) |
| Self-Programming Memory | 64 KB self-programming Flash |
| Boot Code Section | 4 KB |
| SRAM | 4 KB |
| EEPROM | 2 KB |
| Operating Voltage Range | 1.6 V to 3.6 V |
| DMA Controller | 4 channels |
| Event System | 8 channels |
| Package | 64-QFN (9 x 9 mm) |
| Mounting Type | Surface Mount |
| Product Family | AVR XMEGA A3 |
| Power Class | Low-power microcontroller |
| Manufacturer Product Page | ATxmega64A3 |
ATXMEGA64A3-MH 64-qfn (9 x 9 mm) Pin Configuration Guide
Pin configuration for ATXMEGA64A3-MH (64-qfn (9 x 9 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 ATXMEGA64A3-MH.
Refer to the datasheet for full pin configuration.
Typical Applications
ATXMEGA64A3-MH is suitable for 6 applications: Industrial Sensor Acquisition, Low-Power Control Node, Communication Controller, Data Acquisition and Logging, USB Peripheral Product, Precision Timing Control.
Industrial Sensor Acquisition
The ATXMEGA64A3-MH fits industrial sensor-acquisition systems that require local conversion, filtering, and control within a 1.6 V to 3.6 V supply range. Its four-channel DMA controller can move sampled data between memory and peripherals with less CPU intervention, while the eight-channel event system supports coordinated timing between sensors and control functions. The 32 MHz core provides up to 32 MIPS throughput for filtering and state-machine logic. Designers should assign DMA channels and event resources from the verified device configuration, isolate noisy analog inputs, and verify the complete 64-QFN land pattern before committing the board layout.
Recommended
Low-Power Control Node
The ATXMEGA64A3-MH is appropriate for a low-power embedded control node that must combine deterministic peripheral handling with a compact 64-QFN footprint. The low-power AVR XMEGA architecture, 1.6 V minimum operating voltage, and event system allow external sensors, timers, and communication devices to be coordinated without moving every event through the main program loop. Its 64 KB Flash provides room for application firmware, configuration, and a dedicated 4 KB boot-code section. Power-budget calculations should include the MCU rail, external sensing circuitry, and any USB circuitry; the actual sleep and active currents remain datasheet-dependent design inputs.
Recommended
Communication Controller
ATXMEGA64A3-MH can serve as the central controller in a communication module when firmware needs moderate processing throughput, event-driven peripheral timing, and mixed memory resources. The 32 MHz AVR core and up to 32 MIPS throughput support protocol handling alongside background acquisition, while the four-channel DMA controller helps transfer buffers efficiently. The 4 KB SRAM should be mapped explicitly for protocol state, packet buffers, and interrupt-safe queues, and the 2 KB EEPROM can retain limited calibration or network parameters. When USB is required, the ATXMEGA64A3U-MH should be evaluated as the more directly aligned same-package option.
Recommended
Data Acquisition and Logging
The ATXMEGA64A3-MH is well matched to compact acquisition and logging systems where sensor data must be buffered and transferred under predictable timing. Four DMA channels support parallel data movement, and the eight-channel event system can coordinate triggers among acquisition, timing, and communication peripherals. With 64 KB Flash, 4 KB SRAM, and 2 KB EEPROM, the device can separate firmware, a boot-code section, volatile working data, and persistent parameters. Designers should size SRAM buffers from worst-case interrupt concurrency and avoid treating EEPROM as unlimited storage; endurance and write timing must be checked in the manufacturer documentation.
Recommended
USB Peripheral Product
A USB-equipped XMEGA A3 design can use the ATXMEGA64A3U-MH as the MCU for peripheral control and USB connectivity while retaining the same 32 MHz and 64 KB Flash class as the target device. This makes the U variant the more appropriate choice when USB is a system requirement, whereas the ATXMEGA64A3-MH serves designs that do not need USB. USB routing requires exact pin-multiplexing verification, controlled impedance, suitable connector protection, and correct bus decoupling. Firmware must account for the added USB peripheral and its interrupt or DMA resources, so the U variant should not be substituted without recompiling and validating the application.
Recommended
Precision Timing Control
The ATXMEGA64A3-MH can serve timing-sensitive control tasks that benefit from the XMEGA event system, multiple timers, and CPU throughput at 32 MHz. The eight-channel event system can route and trigger peripheral actions, reducing software latency compared with polling every event directly in the main loop. Four DMA channels further allow data transfer to overlap with control computation. Clock accuracy, timer resolution, and interrupt latency depend on the selected clock source and prescaler configuration, which must be derived from the manufacturer timing specifications. PCB layout should preserve short clock paths and provide stable decoupling around the exposed thermal pad.
Recommended
Recommended Products Summary
Engineering reference data for ATXMEGA64A3-MH — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATXMEGA64A3U-MH | ATXMEGA64A4-MH | ATXMEGA128A3-MH | ATXMEGA128A4-MH | ATXMEGA64A4U-MH |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-QFN (9 x 9 mm) | 64-QFN (9 x 9 mm) | 64-QFN (9 x 9 mm) | 64-QFN (9 x 9 mm) | 64-QFN (9 x 9 mm) | 64-QFN (9 x 9 mm) |
| Maximum Clock Frequency | 32 MHz | 32 MHz | 32 MHz | 32 MHz | 32 MHz | 32 MHz |
| Program Memory | 64 KB Flash | 64 KB Flash | 64 KB Flash | 128 KB Flash | 128 KB Flash | 64 KB Flash |
| SRAM | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB |
| EEPROM | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB |
| Operating Voltage Range | 1.6 V to 3.6 V | 1.6 V to 3.6 V | 1.6 V to 3.6 V | 1.6 V to 3.6 V | 1.6 V to 3.6 V | 1.6 V to 3.6 V |
| USB Interface | No | Yes | No | No | No | Yes |
| Maximum Throughput | Up to 32 MIPS at 32 MHz | Up to 32 MIPS at 32 MHz | Up to 32 MIPS at 32 MHz | Up to 32 MIPS at 32 MHz | Up to 32 MIPS at 32 MHz | Up to 32 MIPS at 32 MHz |
Key Differentiators
- Base 64 KB Flash configuration without USB (vs ATXMEGA64A3U-MH)
- Lower Flash capacity than the 128 KB XMEGA A3 option (vs ATXMEGA128A3-MH)
- Four-channel DMA and eight-channel event system (vs ATXMEGA64A4-MH)
Design Notes
Use the exact Microchip 64-QFN 9 x 9 mm land pattern and exposed-pad geometry rather than a generic QFN footprint. Place the input and decoupling capacitors close to their assigned supply pins, keep the clock path short, and provide multiple thermal vias beneath the exposed pad. Confirm pin numbering, exposed-pad connection, and via spacing in the package drawing before releasing the PCB files.
Design the MCU rail for the full verified 1.6 V to 3.6 V operating range and include local high-frequency bypass plus bulk energy storage. Separate sensitive analog and digital return paths where practical, and use the event system to move data without excessive polling. Estimated: no thermal or power-loss calculation is provided because the supplied data does not include active current, sleep current, or exposed-pad thermal resistance.
Do not treat a shared 64-QFN package as sufficient proof of interchangeability. Before replacing the target with an A3U, A4, or 128 KB variant, compare the complete pin table, alternate-function mappings, USB requirements, DMA/event resources, timer assignments, boot section, linker memory map, and device-specific startup code. A package-compatible part can still require firmware and PCB-signal reassignment.
Compliance Information
The supplied verified data identifies an industrial-oriented part in one distributor listing but does not provide explicit RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declarations. Compliance fields are therefore marked unknown rather than inferred.
