ATSAM3N2AA-AU - ARM Cortex-M3 48MHz 128KB MCU | Microchip
MPN: ATSAM3N2AA-AU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.2 | $4.20 |
| 10 | $3.78 | $37.80 |
| 100 | $3.36 | $336.00 |
| 500 | $3.02 | $1,510.00 |
| 1,000 | $2.68 | $2,680.00 |
ATSAM3N2AA-AU Overview
A microcontroller unit (MCU) is an integrated circuit that combines a processor core, memory, and peripherals on a single chip, forming the heart of embedded systems. The SAM3N family sits within the broader hierarchy of ARM Cortex-M based flash MCUs, one level below application processors and above 8-bit MCUs, targeting cost-sensitive, low-power industrial and consumer applications.
Key features include the ARM Cortex-M3 revision 2.0 core with the Thumb-2 instruction set, a 24-bit SysTick counter, and a Nested Vector Interrupt Controller (NVIC) for deterministic interrupt handling. The device offers 34 general-purpose I/O lines, an internal oscillator, and pin-to-pin compatibility across the SAM3N memory variants, which simplifies migration between 64 KB, 128 KB, and 256 KB flash options without PCB changes.
Architecturally, the Cortex-M3 Harvard-style core delivers efficient 32-bit computation with low power consumption, operating from 1.8 V to 3.3 V supply rails. The embedded flash supports in-system programming, while peripherals typical of the SAM3N series include USART, SPI, and two-wire interfaces for serial communication.
Typical applications include industrial control nodes, consumer appliances, metering systems, and general-purpose embedded products where 128 KB of flash and a 48 MHz core provide adequate headroom.
Designers should verify the exact peripheral set and pin multiplexing against the manufacturer datasheet before committing the PCB layout, since the 48-pin variant exposes fewer peripheral instances than larger 64-pin or 100-pin SAM3N members.
This page synthesizes distributor pricing, drop-in family alternatives, and practical design guidance not consolidated in the manufacturer datasheet.
Drop-in alternatives for ATSAM3N2AA-AU 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 ATSAM3N2AA-AU (same form factor and footprint) β differing in Core Processor, Packaging, ADC Resolution, Package, Pin Compatibility.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAM3N4AA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAM3N1AA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
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View Datasheet βATSAM3N2AA-AU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M3 revision 2.0 |
| Core Size | 32-bit |
| Maximum Clock Speed | 48 MHz |
| Program Memory Size | 128 KB (128K x 8) FLASH |
| RAM Size | 16K x 8 |
| Number of I/O | 34 |
| Oscillator Type | Internal |
| Supply Voltage | 1.8 V / 3.3 V |
| Instruction Set | Thumb-2 |
| SysTick Counter | 24-bit |
| Interrupt Controller | NVIC (Nested Vector Interrupt Controller) |
| Pin Compatibility | Pin-to-pin compatible across SAM3N family variants |
| Package / Case | 48-LQFP (7x7 mm) |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (TR) |
| Product Series | SAM3N |
ATSAM3N2AA-AU 48-lqfp (7x7 mm) Pin Configuration Guide
Pin configuration for ATSAM3N2AA-AU (48-lqfp (7x7 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 ATSAM3N2AA-AU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM3N2AA-AU is suitable for 6 applications: Industrial Control Nodes, Consumer Appliances, Utility Metering Systems, Embedded Sensor Hubs, Building Automation Peripherals, Handheld and Portable Instruments.
Industrial Control Nodes
The ATSAM3N2AA-AU fits industrial control nodes where deterministic interrupt handling and adequate memory matter more than raw clock speed. Its 48 MHz ARM Cortex-M3 core with the Nested Vector Interrupt Controller (NVIC) gives bounded interrupt latency for control loops, while 128 KB of flash accommodates protocol stacks and field-updatable firmware and 16 KB of SRAM buffers sensor and communication data. With 34 GPIO lines, it directly drives relays, reads encoders, and interfaces with USART, SPI, and two-wire serial peripherals. Operating from a 3.3 V rail, it replaces 8-bit MCUs in PLC I/O modules and motor-control supervisory circuits while keeping power draw low. Designers should budget flash carefully: at 128 KB, larger RTOS-based builds may need the pin-compatible 256 KB ATSAM3N4AA-AU upgrade path.
Recommended
Consumer Appliances
In consumer appliances such as coffee machines, air conditioners, and small kitchen devices, the ATSAM3N2AA-AU offers a cost-effective 32-bit control platform. The internal oscillator removes the need for an external crystal in cost-optimized designs, and Thumb-2 instruction density keeps firmware compact within the 128 KB flash budget. The 48 MHz Cortex-M3 core comfortably handles touch-decoding loops, display refresh, and serial communication with the main appliance controller, while the 1.8 V/3.3 V operating range supports modern low-voltage power trees. The 48-LQFP 7x7 mm package suits compact two-layer or four-layer appliance PCBs, and its pin-to-pin family compatibility means a single PCB can be populated with the 64 KB, 128 KB, or 256 KB variant to serve product tiers without layout changes - a key advantage for appliance platforms with feature-scaled SKUs.
Recommended
Utility Metering Systems
Metering applications - electricity sub-meters, water and gas meter electronics - benefit from the ATSAM3N2AA-AU's combination of low power, adequate memory, and serial connectivity. The 16 KB SRAM holds cumulative register data and communication buffers for protocols such as Modbus over USART, while 128 KB flash stores calibration tables and metrology firmware with room for in-field firmware updates. The Cortex-M3 core at 48 MHz processes pulse counting, CRC computation, and display-driving tasks with margin, and its sleep modes support battery-backed meter operation. The 34 I/O lines interface keypads, LCD segments, and optical communication ports. Because metering products have long lifecycles, the SAM3N family's pin-to-pin compatibility lets manufacturers qualify one PCB with alternate flash sizes as a hedge against end-of-life risk on any single memory variant.
Recommended
Embedded Sensor Hubs
The ATSAM3N2AA-AU serves well as a sensor hub aggregating data from digital sensors over SPI and two-wire (I2C-compatible) interfaces. Its 48 MHz Cortex-M3 core performs filtering, scaling, and threshold logic on streaming sensor data, while the 16 KB SRAM provides adequate ring-buffer capacity for burst captures and the 24-bit SysTick timer supports precise timestamping of sensor events. The 34 GPIO lines allow direct interrupt inputs from multiple sensors plus status output to a host. Flash of 128 KB hosts compensation algorithms and a lightweight communication stack toward a gateway over USART. Operating from 3.3 V simplifies interfacing with common 3.3 V MEMS sensors. For designs accumulating large datasets locally, the pin-compatible ATSAM3N4AA-AU variant doubles code space without PCB rework.
Recommended
Building Automation Peripherals
Building automation peripheral nodes - room controllers, damper actuators, occupancy-based lighting interfaces - leverage the ATSAM3N2AA-AU's balance of performance and cost. The 128 KB flash accommodates a small network stack and application logic, the Cortex-M3 NVIC provides responsive handling of occupancy sensor interrupts, and the USART/SPI/two-wire peripherals connect to transceivers and room display modules. With 34 GPIO, a single device drives actuator H-bridge inputs, status LEDs, and configuration DIP switches without port expanders. The internal oscillator supports cost-sensitive node designs, while 3.3 V operation aligns with standard bus transceiver rails. The SAM3N family's pin-to-pin compatibility across 64 KB, 128 KB, and 256 KB flash variants allows one certified PCB layout to serve multiple node types across a building automation portfolio, reducing qualification and inventory overhead.
Recommended
Handheld and Portable Instruments
Portable instruments such as handheld meters, testers, and data loggers choose the ATSAM3N2AA-AU for its low power consumption and 32-bit processing headroom. The Cortex-M3 core executes measurement math, averaging, and calibration routines efficiently at 48 MHz, then the system can drop into sleep modes between readings to extend battery life - important in devices powered by AA cells or lithium coin cells. The 128 KB flash supports menu-driven user interfaces on segment or small graphic displays, and 16 KB SRAM stores logged samples before upload over USART. The internal oscillator and 48-LQFP 7x7 mm package enable compact, two-board handheld architectures. Designers targeting high-sample-rate logging should evaluate the pin-compatible ATSAM3N4AA-AU, whose 256 KB flash permits larger lookup tables and logging buffers without layout changes.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM3N2AA-AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3N4AA-AU | ATSAM3N1AA-AU |
|---|---|---|---|
| Package | 48-LQFP (7x7 mm) | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same |
| Brand | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) |
| Core / Max Frequency | ARM Cortex-M3, 48 MHz | ARM Cortex-M3, 48 MHz | ARM Cortex-M3, 48 MHz |
| Flash Memory | 128 KB (128K x 8) | 256 KB | 64 KB |
| SRAM | 16K x 8 | 16K x 8 | 16K x 8 |
| Number of I/O | 34 | 34 | 34 |
| Supply Voltage | 1.8 V / 3.3 V | 1.8 V / 3.3 V | 1.8 V / 3.3 V |
Key Differentiators
- Balanced mid-memory position in the SAM3N ladder (vs ATSAM3N1AA-AU)
- Cost-efficient path for large firmware (vs ATSAM3N4AA-AU)
- Pin-to-pin family compatibility (vs ATSAM3N4AA-AU and ATSAM3N1AA-AU)
Design Notes
The ATSAM3N2AA-AU operates from 1.8 V or 3.3 V supplies per distributor specifications. When powering from a switching regulator, add an RC or ferrite-bead filter between the DC-DC output and the MCU supply pins to reduce ripple on the analog supply domains. Decouple each VDD pin with 100 nF ceramic capacitors placed within 2 mm of the pin, plus one bulk 4.7-10 uF capacitor near the device. Consult the SAM3N datasheet power-supply section for per-domain decoupling requirements before finalizing the power tree.
For the 48-LQFP (7x7 mm) footprint, keep crystal circuits (if used in addition to the internal oscillator) as short as possible with a ground guard ring. Route the 34 GPIO with care around high-current switching traces to prevent crosstalk into analog inputs; assign noisy functions (relay drive, PWM) to pins furthest from the oscillator and analog domains. Provide at least one via per decoupling capacitor to the ground plane. The pin-to-pin family compatibility means the same layout must accommodate 64/128/256 KB variants - verify all multiplexed functions for every planned variant.
A frequent migration mistake is assuming all SAM3N variants expose identical peripheral instances; the 128 KB ATSAM3N2AA variant may differ from the 256 KB ATSAM3N4AA in peripheral count even though pinout matches. Always cross-check the peripheral summary table in the SAM3N family datasheet for the specific variant. Additionally, the suffix -AU denotes package/temperature coding - confirm the ordering code matches your temperature requirement, and never mix Tape & Reel (TR) and tray stock assumptions in production planning without confirming packaging.
Compliance Information
Compliance data was not present in the provided verified web data. Modern Microchip/Atmel parts are typically RoHS compliant, but this must be confirmed on the official Microchip product page before use in regulated applications.