ATXMEGA256A3U-AN - 32MHz 256KB Flash 8/16-bit AVR MCU | Microchip
Référence : ATXMEGA256A3U-AN ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $9.33 | $9,33 |
| 10 | $8.55 | $85,50 |
| 100 | $7.62 | $762,00 |
| 500 | $6.85 | $3 425,00 |
| 1 000 | $6.1 | $6 100,00 |
ATXMEGA256A3U-AN Présentation
Background Knowledge: An 8/16-bit AVR XMEGA microcontroller is a member of the RISC microcontroller family, sitting in the hierarchy 8-bit MCU -> AVR core -> XMEGA family -> A3U series -> 64-pin TQFP class. It executes most instructions in a single clock cycle, providing close to 1 MIPS per MHz, and combines deterministic interrupt response with rich analog and digital peripherals for embedded control.
Key features include 256 KB Flash with 8 KB boot section, 4 KB EEPROM endurance up to 100,000 cycles, 16 KB SRAM, an internal 32 MHz calibrated oscillator, multiple USART/SPI/TWI interfaces, and a 12-bit ADC with up to 2 MSPS sampling. The A3U suffix designates the USB-equipped sub-family with hardware AES and DES crypto engines. The 1.6 V to 3.6 V supply range supports battery and industrial 3.3 V rails, while sleep current under 1 µA with RTC running enables energy-harvesting and portable designs.
Typical applications include USB peripherals, building and industrial automation, motor control, sensor hubs, and human-machine interface (HMI) panels. The integrated full-speed USB 2.0 device interface is widely used for HID, CDC, and vendor-class peripherals without an external transceiver. Hardware AES/DES acceleration offloads secure communication tasks from the CPU, while the 12-bit ADC and high-resolution timers simplify BLDC and stepper motor control loops.
Designers should size decoupling per 64-pin TQFP power pins and follow the Atmel AVR1003 application note for USB hardware design. Use the Atmel AVR Studio / Microchip Studio toolchain with the AVR Dragon or JTAGICE3 for in-system debug. The XMEGA A3U datasheet and AVR1020 migration note are the authoritative references for peripheral mapping and migration from earlier A3 (non-U) parts.
Alternatives de remplacement direct pour ATXMEGA256A3U-AN — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec ATXMEGA256A3U-AN (même facteur de forme et même empreinte) — différant par Operating Temperature, Program Memory (Flash), RoHS Status, USB Interface.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
ATXMEGA192A3U-AN
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ATXMEGA128A3U-AN
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ATXMEGA64A3U-AN
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ATXMEGA256A3U-AU
✅ Remplacement direct✓ En stock
$9.1 / unité
Voir la fiche technique →ATXMEGA256A3U-AN Valeurs maximales et caractéristiques électriques
| Product Type | AVR XMEGA A3U Microcontroller |
| Architecture | 8/16-bit AVR enhanced RISC |
| Core | AVR (single-cycle instructions, 32 MHz) |
| Fréquence d'horloge maximale | 32 MHz |
| Throughput | Up to 32 MIPS |
| Program Memory (Flash) | 256 KB (128K x 16), with 8 KB boot section |
| SRAM | 16 KB |
| EEPROM | 4 KB |
| DMA Controller | 4-channel |
| Event System | 8-channel |
| USB Interface | USB 2.0 Full-Speed Device (A3U sub-family) |
| Cryptographic Engine | AES and DES hardware acceleration |
| Supply Voltage (Vcc) | 1.6 V to 3.6 V |
| Température de fonctionnement | -40 °C to +105 °C (industrial) |
| Boîtier | 64-pin TQFP (14x14 mm) |
| Type de montage | Surface Mount |
| Statut RoHS | Compliant (Mouser listing: GREEN) |
| Niveau MSL | 3 (per TQFP JEDEC J-STD-020) |
Configuration des broches de ATXMEGA256A3U-AN
| Broche 1 | VCC — Digital supply voltage |
| Broche 2 | PA0 — Port A bit 0 (GPIO / ADC0) |
| Broche 3 | PA1 — Port A bit 1 (GPIO / ADC1) |
| Broche 4 | PA2 — Port A bit 2 (GPIO / ADC2) |
| Broche 5 | PA3 — Port A bit 3 (GPIO / ADC3) |
| Broche 6 | PA4 — Port A bit 4 (GPIO / ADC4) |
| Broche 7 | PA5 — Port A bit 5 (GPIO / ADC5) |
| Broche 8 | PA6 — Port A bit 6 (GPIO / ADC6) |
| Broche 9 | PA7 — Port A bit 7 (GPIO / ADC7) |
| Broche 10 | GND — Ground |
| Broche 11 | PB0 — Port B bit 0 (GPIO) |
| Broche 12 | PB1 — Port B bit 1 (GPIO) |
| Broche 13 | PB2 — Port B bit 2 (GPIO) |
| Broche 14 | PB3 — Port B bit 3 (GPIO) |
| Broche 15 | PB4 — Port B bit 4 (GPIO) |
| Broche 16 | PB5 — Port B bit 5 (GPIO) |
| Broche 17 | PB6 — Port B bit 6 (GPIO) |
| Broche 18 | PB7 — Port B bit 7 (GPIO) |
| Broche 19 | PC0 — Port C bit 0 (GPIO) |
| Broche 20 | PC1 — Port C bit 1 (GPIO) |
| Broche 21 | PC2 — Port C bit 2 (GPIO) |
| Broche 22 | PC3 — Port C bit 3 (GPIO) |
| Broche 23 | PC4 — Port C bit 4 (GPIO) |
| Broche 24 | PC5 — Port C bit 5 (GPIO) |
| Broche 25 | PC6 — Port C bit 6 (GPIO) |
| Broche 26 | PC7 — Port C bit 7 (GPIO) |
| Broche 27 | VCC — Digital supply voltage |
| Broche 28 | PD0 — Port D bit 0 (GPIO) |
| Broche 29 | PD1 — Port D bit 1 (GPIO) |
| Broche 30 | PD2 — Port D bit 2 (GPIO) |
| Broche 31 | PD3 — Port D bit 3 (GPIO) |
| Broche 32 | PD4 — Port D bit 4 (GPIO) |
| Broche 33 | PD5 — Port D bit 5 (GPIO) |
| Broche 34 | PD6 — Port D bit 6 (GPIO) |
| Broche 35 | PD7 — Port D bit 7 (GPIO) |
| Broche 36 | PE0 — Port E bit 0 (GPIO / OC0A / USART0 RX) |
| Broche 37 | PE1 — Port E bit 1 (GPIO / OC0B / USART0 TX) |
| Broche 38 | PE2 — Port E bit 2 (GPIO / OC0C) |
| Broche 39 | PE3 — Port E bit 3 (GPIO) |
| Broche 40 | PE4 — Port E bit 4 (GPIO) |
| Broche 41 | PE5 — Port E bit 5 (GPIO) |
| Broche 42 | PE6 — Port E bit 6 (GPIO) |
| Broche 43 | PE7 — Port E bit 7 (GPIO) |
| Broche 44 | AVCC — Analog supply voltage |
| Broche 45 | PF0 — Port F bit 0 (GPIO / ADC8 / AREF) |
| Broche 46 | PF1 — Port F bit 1 (GPIO / ADC9) |
| Broche 47 | PF2 — Port F bit 2 (GPIO / ADC10) |
| Broche 48 | PF3 — Port F bit 3 (GPIO / ADC11) |
| Broche 49 | PF4 — Port F bit 4 (GPIO / JTAG TCK / ADC12) |
| Broche 50 | PF5 — Port F bit 5 (GPIO / JTAG TMS / ADC13) |
| Broche 51 | PF6 — Port F bit 6 (GPIO / JTAG TDO / ADC14) |
| Broche 52 | PF7 — Port F bit 7 (GPIO / JTAG TDI / ADC15) |
| Broche 53 | GND — Ground |
| Broche 54 | PQ0 — Port Q bit 0 (USB D-) |
| Broche 55 | PQ1 — Port Q bit 1 (USB D+) |
| Broche 56 | PQ2 — Port Q bit 2 (USB VBUS / GPIO) |
| Broche 57 | PQ3 — Port Q bit 3 (USB ID / GPIO) |
| Broche 58 | RESET — Reset input (active low) |
| Broche 59 | PR0 — Port R bit 0 (PDI DATA / GPIO) |
| Broche 60 | PR1 — Port R bit 1 (PDI CLK / GPIO) |
| Broche 61 | XTAL1 — Crystal oscillator input |
| Broche 62 | XTAL2 — Crystal oscillator output |
| Broche 63 | AREF — ADC reference voltage reference |
| Broche 64 | AGND — Analog ground |
Applications typiques
ATXMEGA256A3U-AN convient pour 6 applications: USB HID / CDC Peripherals, Building & Industrial Automation, BLDC / Stepper Motor Control, Human-Machine Interface (HMI) Panels, Secure Sensor / Data Logger Nodes, Portable Test & Measurement Instruments.
USB HID / CDC Peripherals
The ATXMEGA256A3U-AN's on-chip USB 2.0 Full-Speed device controller makes it a natural fit for USB HID, CDC, and vendor-class peripherals. The A3U family integrates the USB transceiver and SIE, eliminating external PHY parts; the AVR core at 32 MHz / 32 MIPS easily handles USB interrupt latency and protocol stacks such as LUFA or Atmel USB. With 256 KB Flash and 16 KB SRAM, full HID/CDC stacks fit comfortably alongside application code, and the hardware AES/DES engine can secure vendor-class payloads. Designers should follow AVR1003 for D+/D- layout, place a 22 µΩ ferrite on VBUS, and supply VBUS through the internal 3.3 V regulator for self-powered designs.
Recommandé
Building & Industrial Automation
Industrial automation gateways, sensor hubs, and HVAC controllers benefit from the ATXMEGA256A3U-AN's 105 °C industrial temperature rating, 1.6 V to 3.6 V supply range, and rich peripherals. The 12-bit ADC, multiple USART/SPI/TWI interfaces, and 4-channel DMA controller can scan sensor arrays while the CPU handles protocol stacks. The 256 KB Flash accommodates Modbus, BACnet, or proprietary fieldbus firmware, and 16 KB SRAM handles network buffering. Hardware AES/DES acceleration is useful for secured industrial IoT links, and the 8-channel event system provides deterministic inter-peripheral signalling without CPU load.
Recommandé
BLDC / Stepper Motor Control
The ATXMEGA256A3U-AN is well-suited to BLDC and stepper motor drives thanks to its high-resolution timers, PWM channels, and fast 12-bit ADC. The 32 MHz core delivers 32 MIPS, sufficient for field-oriented control (FOC) loops at typical PWM carrier frequencies. The 4-channel DMA controller offloads ADC-to-memory transfers and minimizes control-loop jitter. The event system routes timer triggers to ADC conversions deterministically, while the AES engine can encrypt communication between the motor drive and a higher-level controller. The 64-pin TQFP footprint exposes enough I/O for three-phase gate drivers plus comms and feedback.
Recommandé
Human-Machine Interface (HMI) Panels
For HMI panels with TFT/LCD displays and touch sensing, the ATXMEGA256A3U-AN offers 256 KB Flash and 16 KB SRAM to host graphics libraries, while its SPI/TWI masters can drive displays and capacitive touch controllers. The XMEGA event system supports direct DMA-driven display refresh, offloading CPU time. USB device mode enables panel configuration and firmware update from a host PC, and the hardware AES engine secures credential storage. Industrial 105 °C operation supports control cabinet installations without additional thermal conditioning.
Recommandé
Secure Sensor / Data Logger Nodes
Battery-powered secure sensor nodes and data loggers leverage the ATXMEGA256A3U-AN's hardware AES/DES engine, deep-sleep current under 1 µA with RTC running, and 256 KB Flash for buffering. The 4 KB EEPROM provides non-volatile parameter storage, while the 12-bit ADC and event system enable low-power sensor sampling. USB device mode simplifies in-field firmware updates, and the AES engine accelerates encrypted MQTT/HTTPS payload preparation when paired with a network co-processor. The wide 1.6-3.6 V supply range supports 3.6 V Li-coin and 3.3 V regulated rails.
Recommandé
Portable Test & Measurement Instruments
Handheld test instruments, data acquisition modules, and USB probes leverage the ATXMEGA256A3U-AN's USB 2.0 FS device interface for high-speed PC connectivity, 12-bit ADC for measurement, and AES engine for protected firmware. The 256 KB Flash and 16 KB SRAM accommodate signal-processing routines and look-up tables, while the event system synchronizes ADC sampling to PWM or external triggers. Industrial 105 °C operation supports laboratory and field use without active cooling.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour ATXMEGA256A3U-AN — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | ATXMEGA192A3U-AN | ATXMEGA128A3U-AN | ATXMEGA64A3U-AN | ATXMEGA256A3U-AU |
|---|---|---|---|---|---|
| Package | 64-pin TQFP (14x14 mm) | 64-pin TQFP (14x14 mm) - same | 64-pin TQFP (14x14 mm) - same | 64-pin TQFP (14x14 mm) - same | 64-pin TQFP (14x14 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 256 KB | 192 KB | 128 KB | 64 KB | 256 KB |
| SRAM | 16 KB | 16 KB | 16 KB | 16 KB | 16 KB |
| Maximum Clock Frequency | 32 MHz | 32 MHz | 32 MHz | 32 MHz | 32 MHz |
| Supply Voltage | 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 |
| Operating Temperature | -40 °C to +105 °C | -40 °C to +105 °C | -40 °C to +105 °C | -40 °C to +105 °C | -40 °C to +85 °C |
| USB 2.0 Full-Speed Device | Yes (on-chip) | Yes (on-chip) | Yes (on-chip) | Yes (on-chip) | Yes (on-chip) |
| AES / DES Hardware Engine | Yes | Yes | Yes | Yes | Yes |
Principaux différenciateurs
- Largest Flash density in the 64-pin TQFP AVR XMEGA A3U family (vs ATXMEGA192A3U-AN)
- Industrial 105 °C temperature grade vs 85 °C commercial (vs ATXMEGA256A3U-AU)
- On-chip USB 2.0 Full-Speed + hardware AES/DES (vs ATXMEGA256A3BU-MH)
Notes de conception
Place a 100 nF decoupling capacitor as close as possible to each VCC/AVCC pin (64-pin TQFP has multiple VCC/AVCC pins). Add a bulk 4.7 µF to 10 µF tantalum or ceramic capacitor on the main 3.3 V rail. The XMEGA A3U integrates an internal 1.8 V LDO; route it to the internal logic supply and bypass with 1 µF. For USB-powered designs, ensure VBUS is monitored via the USB sense pin and use the internal regulator to deliver 3.3 V to the rest of the circuit.
The 64-pin TQFP (14x14 mm) is a high-density package; use 0.4 mm pitch traces and a 4-layer PCB with a dedicated ground plane for signal integrity. Route the USB D+/D- pair as a 90 Ω differential pair, length-matched within 1 mm, and keep them away from switching nodes. Per AVR1003, place the USB ferrite bead and ESD protection diode near the USB connector. The PDI DATA/CLK pins should be accessible for in-circuit debug using the AVR Dragon, JTAGICE3, or Atmel-ICE.
Do not confuse ATXMEGA256A3U (non-USB) with ATXMEGA256A3U (USB) — the suffix 'U' denotes the USB-equipped variant. Verify that the boot section (8 KB) is correctly sized for your bootloader, and lock bits are set after programming to protect firmware. When migrating from A3 to A3U per AVR1020 (Microchip doc8416), check LVTTL/LVCMOS compatibility for VCC > 2.7 V and re-validate peripheral mappings. The JTAG and PDI debug interfaces share pins on port F; avoid using PF4-PF7 as GPIO if JTAG is required.
The XMEGA 12-bit ADC achieves best performance with a clean AREF reference; place a 10 nF to 100 nF ceramic bypass on AREF and keep analog traces away from the USB, crystal, and PWM outputs. Enable the on-chip offset/gain cancellation and average 4 or more samples for high-precision measurements. For motor control, use the event system to synchronize ADC conversions to PWM center-aligned triggers, minimizing switching noise in the sample window.
Informations de conformité
RoHS compliant and lead-free per the Mouser 'GREEN' listing and Microchip product page. AEC-Q100 is not applicable — automotive qualification is not declared for this AVR XMEGA A3U part; for automotive applications, use an AEC-Q100-qualified Microchip MCU such as the ATSAM E70/S70 family. Halogen-free status and full REACH declarations should be confirmed via the Microchip material declaration documents.
