ATSAM3N0AA-AU - 48MHz Cortex-M3 MCU 32KB Flash | Microchip
MPN: ATSAM3N0AA-AU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.3 | $3.30 |
| 10 | $3.14 | $31.40 |
| 100 | $2.89 | $289.00 |
| 500 | $2.72 | $1,360.00 |
| 1,000 | $2.58 | $2,580.00 |
ATSAM3N0AA-AU Overview
A microcontroller (MCU) is a single integrated circuit that combines a processor core, memory, and programmable peripherals into one chip, forming the lowest tier of the embedded processing hierarchy: Cortex-M3 core -> ARM-based Flash MCU -> microcontroller -> semiconductor. The SAM3N series belongs to Microchip's SAM3 family of ARM-based Flash microcontrollers and targets cost-sensitive, high-volume embedded applications.
Key features include the ARM Cortex-M3 revision 2.0 core with Thumb-2 instruction set, a 24-bit SysTick timer, and a Nested Vector Interrupt Controller (NVIC). The device operates from 1.62V to 3.6V (1.8V/2.5V/3.3V supply classes) and is rated for industrial temperature operation. The -AU suffix denotes a 48-pin LQFP in a green, RoHS-compliant package supplied in trays.
Architecturally, the Cortex-M3 Harvard core delivers deterministic single-cycle Flash execution with efficient Thumb-2 code density, while the NVIC provides low-latency, prioritized interrupt handling essential for real-time control. The SAM3N series is pin-to-pin compatible with the SAM3S series and with legacy SAM7S devices (48- and 64-pin versions), enabling seamless migration paths for flash density and peripheral upgrades without PCB rework.
Typical applications include industrial control and automation nodes, consumer appliance interfaces, metering front-ends, and cost-optimized IoT sensor endpoints where 32-bit performance is needed at 8/16-bit MCU price points.
Design consideration: the ATSAM3N0AA-AU has no USB peripheral (that belongs to other SAM3 variants), so designs requiring high-speed USB should select an appropriate sibling part; also budget Flash and SRAM margins carefully since 32 KB Flash is the entry point of the family.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATSAM3N0AA-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 ATSAM3N0AA-AU (same form factor and footprint) β differing in Core Processor, Package / Case, Pin Compatibility, Program Memory Size, RAM Size.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAM3N0BA-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
Contact for price
View Datasheet βATSAM3N1BA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$2.85 / Unit
View Datasheet βATSAM3S2AA-AU
β Drop-Inπ Reference alternative (not in catalog)
ATSAM3S4AA-AU
β Drop-Inπ Reference alternative (not in catalog)
ATSAM3N0AA-AU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M3 revision 2.0 |
| Core Size | 32-bit |
| Maximum Clock Frequency | 48 MHz |
| Flash Memory | 32 KB (32K x 8) |
| Instruction Set | Thumb-2 |
| SysTick Timer | 24-bit |
| Interrupt Controller | NVIC (Nested Vector Interrupt Controller) |
| Supply Voltage | 1.8 V / 2.5 V / 3.3 V |
| Package | 48-LQFP (7x7 mm) |
| Mounting Type | Surface Mount |
| Terminal Form | Gull Wing |
| Package Shape | Square (LFQFP) |
| Temperature Grade | Industrial |
| Package Color / Compliance | Green, RoHS (LQFP, Grn, IT, MRL a) |
| Packaging | Tray |
ATSAM3N0AA-AU green, rohs (lqfp, grn, it, mrl a) Pin Configuration Guide
Pin configuration for ATSAM3N0AA-AU (green, rohs (lqfp, grn, it, mrl a) 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 ATSAM3N0AA-AU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM3N0AA-AU is suitable for 6 applications: Industrial Control and Automation, Cost-Sensitive Consumer Appliances, Metering and Smart Energy Front-Ends, IoT Sensor Endpoints, Legacy SAM7S Design Migration, Test and Measurement Auxiliary Control.
Industrial Control and Automation
The ATSAM3N0AA-AU fits industrial control nodes because its 48 MHz Cortex-M3 core provides deterministic real-time interrupt response through the NVIC, while its industrial temperature grade and 1.8V-3.6V tolerance suit noisy factory environments. In a typical PLC expansion module or motor-control supervisory node, the MCU runs the control loop from single-cycle Flash while communicating over UART/SPI/I2C links. The 32 KB Flash holds protocol stacks and control code comfortably for fixed-function nodes; the 24-bit SysTick timer provides a preciseRTOS tick. Unlike 8-bit MCUs, the Thumb-2 instruction set delivers control arithmetic with fewer cycles, improving loop latency at the same clock. Estimated benefit: a PID loop executing in tens of microseconds at 48 MHz without an external coprocessor.
Recommended
Cost-Sensitive Consumer Appliances
The SAM3N series was explicitly engineered, per the Atmel datasheet, with 'an aggressive price point and high level of integration' that pushes its use into cost-sensitive, high-volume consumer applications. At roughly $3.30 per unit (as of 2026-09-19), the ATSAM3N0AA-AU brings 32-bit computing to appliance user interfaces, small-home-appliance control boards, and toy/interactive products where an 8-bit MCU would struggle with UI rendering or communication stacks. The 48-pin 7x7 mm LQFP provides enough GPIO for keypad scanning, LED segments, and display control while remaining hand-solderable for prototyping. The green RoHS package simplifies global regulatory compliance for consumer SKUs, and tray packaging suits medium-volume SMT lines.
Recommended
Metering and Smart Energy Front-Ends
Utility metering subsystems benefit from the ATSAM3N0AA-AU's combination of a 32-bit Cortex-M3 core for consumption calculations and low 1.8V/2.5V/3.3V supply flexibility for battery-backed or transformer-coupled designs. In an energy-meter communication module, the MCU aggregates pulse or SPI data from a metering AFE, formats frames, and drives an IR/RS-485 UART link - a workload well matched to 48 MHz and 32 KB Flash. The NVIC's low-latency, prioritized interrupts ensure sampling timers are serviced jitter-free, which matters for accumulation accuracy. Pin compatibility with the SAM3S family lets the same PCB scale to parts with integrated DACs or more Flash for DLMS/COSEM stacks without layout changes.
Recommended
IoT Sensor Endpoints
For battery-powered IoT sensor endpoints, the ATSAM3N0AA-AU offers a favorable active-performance-per-mA profile: the Cortex-M3 completes sensing, filtering, and packet-formation tasks quickly at 48 MHz and can then enter low-power modes, reducing average current versus a slower 8-bit core that stays awake longer. The 32 KB Flash stores sensor drivers plus a lightweight protocol stack, and the 1.62V-3.6V operating window allows direct powering from a 3V coin cell via an LDO or from two AA cells. Typical node architecture places the SAM3N0AA between an I2C/SPI sensor and a UART-connected radio module, with the 24-bit SysTick providing a stable timebase for duty-cycled sampling. Firmware margin should be watched as stacks grow; the pin-compatible 64 KB ATSAM3N1AA-AU is the no-rework upgrade.
Recommended
Legacy SAM7S Design Migration
The ATSAM3N0AA-AU is a documented migration target for legacy Atmel SAM7S designs: per the datasheet, SAM3N is pin-to-pin compatible with SAM7S legacy products in 48- and 64-pin versions. Engineering teams facing SAM7S end-of-life or supply constraints can drop the SAM3N0AA onto an existing 48-pin LQFP footprint, retaining the PCB while gaining a modern Cortex-M3 revision 2.0 core, Thumb-2 code density, and continued Microchip lifecycle support. Software requires porting from ARM7TDMI to Cortex-M3 (new interrupt controller model via NVIC, SysTick replacing manual timer setup), but peripheral-level register interfaces remain familiar across the SAM family. This makes the part a low-risk bridge that preserves board investments while modernizing the processing core.
Recommended
Test and Measurement Auxiliary Control
Bench instruments, dongles, and sensor-conditioning boards frequently need a small auxiliary MCU for housekeeping tasks - front-panel key scanning, status LEDs, fan monitoring, and host communication. The ATSAM3N0AA-AU serves this role economically: its 48 MHz Cortex-M3 outperforms typical supervisory 8-bit MCUs, its NVIC prioritizes a periodic sampling interrupt above UART traffic, and its industrial temperature grade suits equipment that must survive warm enclosures. The 48-LQFP's 0.5 mm lead pitch is standard for automated assembly, and the green package aligns with most OEM environmental policies. With 32 KB Flash, firmware for a full command parser plus SPI bridge to the instrument's main processor fits with headroom; estimates suggest sub-20 KB for a typical command/telemetry application.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM3N0AA-AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3N0BA-AU | ATSAM3N1AA-AU | ATSAM3N1BA-AU | ATSAM3S2AA-AU | ATSAM3S4AA-AU |
|---|---|---|---|---|---|---|
| Package | 48-LQFP (7x7 mm) | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same | 48-LQFP (7x7 mm) - same (pin-to-pin per datasheet) | 48-LQFP (7x7 mm) - same (pin-to-pin per datasheet) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | ARM Cortex-M3 rev 2.0 | ARM Cortex-M3 | ARM Cortex-M3 | ARM Cortex-M3 | ARM Cortex-M3 | ARM Cortex-M3 |
| Max Clock Frequency | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz | 48 MHz |
| Flash Memory | 32 KB | 32 KB | 64 KB | 64 KB | 32 KB | 64 KB |
| Series Peripherals | SAM3N (base set) | SAM3N (base set) | SAM3N (base set) | SAM3N (base set) | SAM3S (richer peripheral set) | SAM3S (richer peripheral set) |
| Series Pin Compatibility | SAM3S / SAM7S (48-pin) compatible | SAM3N family - full compatibility | SAM3N family - full compatibility | SAM3N family - full compatibility | SAM3N compatible per datasheet | SAM3N compatible per datasheet |
Key Differentiators
- Lowest-cost entry to 32-bit SAM3 performance (vs ATSAM3S2AA-AU)
- In-family no-rework Flash upgrade path (vs ATSAM3N1AA-AU)
- Legacy SAM7S migration target (vs ATSAM3S4AA-AU)
Design Notes
Verify memory margins before locking the ATSAM3N0AA-AU into production: 32 KB Flash is the entry point of the SAM3N family. Keep projected code size under roughly 26 KB (80% utilization) to leave space for field updates and bug fixes. If your application needs USB, note that the SAM3N series does not integrate the high-speed USB transceiver that other SAM3 family members provide - selecting this part for a USB application is a common sourcing-era mistake. Confirm the exact SRAM requirement of your protocol stacks against the datasheet memory map before finalizing the BOM.
The 48-LQFP (7x7 mm, 0.5 mm lead pitch) lands on a standard 48-LQFP footprint; because the SAM3N series is pin-to-pin compatible with SAM3S and SAM7S 48-pin parts, design the land pattern once and document alternate BOM line items (ATSAM3N0BA-AU, ATSAM3N1AA-AU, ATSAM3S2AA-AU) for sourcing flexibility. Place 100 nF ceramic decoupling capacitors at opposite corners of the package plus one bulk capacitor per supply rail, with short, low-inductance traces to the VDDIO/VDDCORE pins. Follow Microchip's SAM3N hardware design guidelines for oscillator and reset network values.
The Cortex-M3 core at 48 MHz produces fast edges on GPIO; for boards driving cables or long traces, enable the pins' controlled slew-rate settings where supported and add series termination (22-33 ohm) on clock and UART lines leaving the board. Keep the crystal or external clock traces short and guarded by ground, since the NVIC's low interrupt latency will faithfully capture glitches if clock integrity is poor. For mixed analog/digital nodes, assign SAM3N ground reference separation consistent with Microchip's application schematics in the SAM3N family datasheet typical applications.
Compliance Information
DigiKey/Mouser list the part as 'LQFP, Grn, IT, MRL a' - 'Grn' denotes Microchip's green RoHS-compliant package. Formal REACH and conflict-minerals declarations should be obtained from Microchip's compliance portal.