ATXMEGA64B3-MH - 32MHz 64KB AVR Microcontroller | Microchip
MPN: ATXMEGA64B3-MH ✓ ActiveATXMEGA64B3-MH Overview
An 8/16-bit AVR microcontroller is a programmable semiconductor that combines a CPU core, embedded Flash program memory, data memory, peripherals, and communication interfaces in one package. The ATXMEGA B3 family belongs to the AVR microcontroller, embedded processor, and 8/16-bit MCU hierarchy. Its combination of self-programming Flash, EEPROM, DMA, event-system hardware, USB connectivity, and LCD control makes it suitable for compact embedded systems that need deterministic peripheral handling without a separate host processor.
Key features include 64 KB of Flash for firmware, 4 KB of SRAM, and 2 KB of nonvolatile EEPROM. The USB Full-Speed interface supports direct USB-connected equipment, while the DMA controller and event system allow data movement and peripheral events to be handled more efficiently by the CPU. The integrated 4x25 segment LCD controller can drive suitable segmented displays, reducing the need for external display-driver ICs in metering and human-interface designs.
The ATXMEGA64B3 architecture combines an AVR CPU operating at up to 32 MHz with dedicated event, DMA, timer, communications, and USB resources. Its maximum throughput of 32 MIPS supports responsive control and data-processing tasks. The device is available in a 64-QFN (9x9) package, making it appropriate for compact, surface-mounted industrial, utility-metering, home-automation, medical, and USB-connectivity products where board area is constrained.
Typical applications include utility meters, home-automation controllers, climate-control panels, industrial controls, sports equipment, electronic tokens, medical equipment, USB connectivity products, power tools, and fire-alarm systems. Its integrated USB device interface is particularly useful for configuration, firmware update, data logging, or direct connectivity to a host system.
When designing a PCB around ATXMEGA64B3-MH, follow the manufacturer pin, package, decoupling, and layout instructions exactly. Check voltage limits and exposed-pad requirements in the datasheet, preserve the power and ground distribution architecture, and validate USB signal routing and firmware support for the intended host. Use the manufacturer datasheet pin-description table when assigning tracks and programming the device.
This product page combines manufacturer specifications, distributor package and availability details, practical application guidance, design cautions, and same-family replacement analysis. It is intended to help engineers identify whether the ATXMEGA64B3-MH architecture, memory configuration, package, USB capability, and peripheral mix fit a specific embedded design before finalizing the schematic and firmware.
Drop-in alternatives for ATXMEGA64B3-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 ATXMEGA64B3-MH (same form factor and footprint) — differing in Package.
ATXMEGA128B3-MH
✅ Drop-In📋 Reference alternative (not in catalog)
ATXMEGA128D3-MH
✅ Drop-In📋 Reference alternative (not in catalog)
ATXMEGA256C3-MHR
✅ Drop-In📋 Reference alternative (not in catalog)
ATXMEGA64A3-AU
✅ Drop-InContact for price
View Datasheet →ATXMEGA64B3-ANR
✅ Drop-In📋 Reference alternative (not in catalog)
ATXMEGA64B3-MH Maximum Ratings & Electrical Characteristics
| Product Type | 8/16-bit AVR XMEGA B3 microcontroller |
| Maximum Clock Frequency | 32 MHz |
| Maximum Throughput | 32 MIPS at 32 MHz |
| Flash Program Memory | 64 KB (32K x 16) |
| Self-Programming Flash | 64 KB |
| Boot Code Section | 4 KB |
| SRAM | 4 KB |
| EEPROM | 2 KB |
| DMA Controller | 2 channels |
| Event System | 4 channels |
| USB Interface | USB Full-Speed Device |
| LCD Controller | 4x25 segment LCD controller |
| Supply Voltage | 1.6 V to 3.6 V |
| Package | 64-QFN (9x9 mm) |
| Mounting Type | Surface Mount |
| Qualification Status | Green |
ATXMEGA64B3-MH 64-qfn (9x9 mm) Pin Configuration Guide
Pin configuration for ATXMEGA64B3-MH (64-qfn (9x9 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 ATXMEGA64B3-MH.
Refer to the datasheet for full pin configuration.
Typical Applications
ATXMEGA64B3-MH is suitable for 6 applications: USB Utility Metering, Home Automation Controller, Industrial Control Panel, USB Connectivity Product, Climate and Environmental Monitor, Medical and Portable Device.
USB Utility Metering
The ATXMEGA64B3-MH suits compact utility meters that need local measurement control, nonvolatile records, a segmented display, and a direct USB connection. Its 32 MHz AVR core provides up to 32 MIPS throughput, while the USB Full-Speed Device controller enables configuration, data export, and firmware maintenance through a host. The 64 KB Flash, 4 KB SRAM, and 2 KB EEPROM provide useful partitioning for metering code, calibration data, and operating records. The two-channel DMA controller and four-channel event system can also move sampled data and synchronize peripheral events without relying entirely on interrupt service routines. For production designs, verify measurement accuracy, metrology certification, EMC performance, and USB bus-power requirements in the final system.
Recommended
Home Automation Controller
The ATXMEGA64B3-MH can act as the local controller in a home-automation or building-control product combining touch inputs, lighting control, serial sensors, and USB commissioning. Its 8/16-bit AVR architecture runs at up to 32 MHz, providing responsive control without a higher-cost application processor. The event system supports deterministic handling of external signals, while the DMA controller assists with buffered data transfers. A 4x25 segment LCD controller is useful for local status displays where an appropriate glass is selected. The device should be paired with suitable communication transceivers for the chosen field bus or wireless module, and the firmware must coordinate startup, debounce, fault handling, and safe states for connected loads.
Recommended
Industrial Control Panel
The ATXMEGA64B3-MH fits industrial control panels that coordinate sensors, actuators, indicators, service interfaces, and local diagnostics. Its 32 MHz maximum clock supports time-sensitive control tasks, and the integrated event system can connect timer, comparator, and communication events to peripheral actions. The 64 KB self-programming Flash permits field-update capability, while 4 KB SRAM and 2 KB EEPROM support working state and persistent configuration. USB Full-Speed device connectivity can simplify commissioning and service access when enabled by the product's security model. For industrial deployment, place particular emphasis on supply-noise tolerance, watchdog behavior, brownout handling, isolation boundaries, protective components, and the environmental qualification of the complete assembly.
Recommended
USB Connectivity Product
The ATXMEGA64B3-MH is appropriate for compact USB peripherals that combine configuration, data acquisition, and local control. Its native USB Full-Speed Device interface removes the need for a separate USB controller when the required class or vendor protocol can be implemented in firmware. At 32 MHz and up to 32 MIPS throughput, the AVR core can process device tasks while the USB, DMA, and event-system resources handle connected peripherals. The 2 KB EEPROM is useful for configuration identifiers and calibration values, while the self-programming Flash supports firmware maintenance. Board implementation should follow manufacturer recommendations for USB data lines, series impedance, supply decoupling, common-mode considerations, and the exposed thermal pad beneath the QFN package.
Recommended
Climate and Environmental Monitor
The ATXMEGA64B3-MH can serve as the control and communications hub in a climate-control or environmental-monitoring product. It can acquire sensor inputs, apply filtering and compensation, drive a segmented local display, and record operating information in EEPROM. The four-channel event system helps synchronize periodic measurements with timer-driven conversions, while the two-channel DMA controller can reduce CPU overhead during buffered transfers. A 1.6 V to 3.6 V operating range supports low-voltage designs, although the exact regulator and sensor requirements determine actual battery life. Product developers should validate clock accuracy, temperature compensation, low-power behavior, display contrast, sensor isolation, and calibration schedules before production release.
Recommended
Medical and Portable Device
The ATXMEGA64B3-MH can support compact medical or portable equipment where local control, data retention, low-voltage operation, and service connectivity are required. Its 64 KB Flash accommodates application firmware, 4 KB SRAM handles active data, and 2 KB EEPROM preserves configuration or critical parameters. The USB interface can provide a controlled service and data path if the product permits it, while the LCD controller can support a basic local display. For medical use, the MCU choice must be evaluated within the complete risk-management process rather than considered qualified by itself. Confirm electrical isolation, patient-safety boundaries, firmware validation, data integrity, electromagnetic compatibility, and applicable quality requirements for the finished device.
Recommended
Recommended Products Summary
Engineering reference data for ATXMEGA64B3-MH — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATXMEGA128B3-MH | ATXMEGA128D3-MH | ATXMEGA256C3-MHR | ATXMEGA64A3 | ATXMEGA64B3-ANR |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-QFN (9x9 mm) | 64-QFN (9x9 mm) | 64-QFN (9x9 mm) | 64-QFN (9x9 mm) | 64-QFN (9x9 mm) | 64-QFN (9x9 mm) |
| Flash Program Memory | 64 KB | 128 KB | 128 KB | 256 KB | 64 KB | 64 KB |
| Core Type | 8/16-bit AVR | 8/16-bit AVR | 8/16-bit AVR | 8/16-bit AVR | 8/16-bit AVR | 8/16-bit AVR |
Key Differentiators
- Lower Flash configuration with integrated USB and LCD resources (vs ATXMEGA128B3-MH)
- B3-series USB, DMA, event-system, and LCD integration (vs ATXMEGA64A3)
- Substantially lower memory requirement than the C3 alternative (vs ATXMEGA256C3-MHR)
Design Notes
Use the manufacturer land pattern and exposed-pad instructions for the 64-QFN (9x9 mm) package. Place the input, output, and decoupling capacitors close to their designated power pins, provide a low-impedance ground plane, and minimize loop area between each capacitor and the device. Confirm paste volume, solder-mask definition, and thermal-via requirements against the current package drawing before releasing artwork.
Route USB D+ and D- as a controlled-impedance differential pair and keep the pair away from clocks, switching nodes, and noisy analog inputs. Follow the manufacturer's guidance on series resistors, common-mode components, ESD protection, and the relationship between the USB transceiver and ground reference. Validate signal integrity with the intended host, cable, enclosure, and connector configuration.
Budget the 1.6 V to 3.6 V operating range against the exact regulator tolerance, transient response, USB bus-power requirements, and peripheral load. Use local bulk and high-frequency decoupling according to the manufacturer guidance, and verify startup behavior at the minimum and maximum supply levels. The 2 KB EEPROM is useful for configuration, but write-cycle endurance and data-retention policies must be included in the firmware design.
Do not treat a same-family part as an automatic drop-in replacement. Compare the complete ordering suffix, package drawing, exposed-pad connection, power pins, clock pins, USB pins, peripheral multiplexing, memory size, boot section, interrupt vector behavior, and device identification before changing the BOM. Revalidate bootloader logic and application code whenever Flash size or boot configuration differs.
At 32 MHz, package dissipation depends on active peripherals, I/O loading, supply voltage, and ambient temperature rather than processor speed alone. Provide adequate exposed-pad thermal relief and copper area, then confirm steady-state junction temperature in the assembled enclosure. Use the manufacturer electrical characteristics and application guidance for thermal calculations rather than estimating from nominal clock frequency.
Compliance Information
The distributor listing identifies the device as Green, but no individual RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declaration is stated. Confirm current compliance documents with the manufacturer.
