ATSAM3N2BA-AU - 48MHz Cortex-M3 MCU 128KB Flash | Microchip
MPN: ATSAM3N2BA-AU ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.95 | $4.95 |
| 10 | $4.52 | $45.20 |
| 100 | $4.1 | $410.00 |
| 500 | $3.72 | $1,860.00 |
| 1,000 | $3.38 | $3,380.00 |
ATSAM3N2BA-AU Overview
A microcontroller (MCU) is a single-chip computer that integrates a processor core, memory, and peripherals such as timers, communication interfaces, and analog-to-digital converters on one die. Within the MCU hierarchy, the ATSAM3N2BA belongs to the Atmel SAM3N family, a subset of ARM-based 32-bit flash microcontrollers, which in turn sits under the broader category of embedded processors and power-management systems on chip.
Key features include the ARM Cortex-M3 revision 2.0 core with Thumb-2 instruction set, a 24-bit SysTick counter, and a Nested Vector Interrupt Controller (NVIC). The internal oscillator type eliminates the need for an external crystal in many designs, reducing BOM cost. The SAM3N series is explicitly pin-to-pin compatible with the SAM3S series, making it an ideal migration path for cost-sensitive, high-volume applications requiring reduced BOM cost while retaining footprint compatibility.
The 48 MHz Cortex-M3 pipeline provides deterministic interrupt handling via the NVIC, and Thumb-2 code density keeps Flash requirements modest, which is why 128 KB is sufficient for many communication and control stacks. The device operates from 1.8V/3.3V supply domains per distributor listings, covering both battery-friendly and standard 3.3V industrial logic.
Typical applications include industrial automation nodes, consumer electronics, medical device control boards, and cost-sensitive high-volume products where the SAM3N datasheet cites its aggressive price point.
Design consideration: leverage the SAM3S pin compatibility to reserve a layout that can be upgraded to higher-memory SAM3S or SAM3N4 variants without PCB respin.
This page synthesizes verified distributor specifications, same-family drop-in alternatives, and practical design notes not consolidated in a single manufacturer datasheet.
Drop-in alternatives for ATSAM3N2BA-AU — 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 ATSAM3N2BA-AU (same form factor and footprint) — differing in Core Processor, Supply Voltage, Core Size, Flash Memory, Interrupt Controller.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAM3N1BA-AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.85 / Unit
View Datasheet →ATSAM3N4BA-AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
Contact for price
View Datasheet →ATSAM3S2BA-AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$4.66 / Unit
View Datasheet →ATSAM3S4BA-AU
✅ Drop-In ⚠️ 参数待验证📋 Reference alternative (not in catalog)
ATSAM3N2BA-AU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M3 |
| Core Size | 32-bit single core |
| Maximum Clock Speed | 48 MHz |
| Program Memory Size | 128KB (128K x 8) |
| Program Memory Type | FLASH |
| RAM Size | 16K x 8 |
| Number of I/O | 47 |
| Supply Voltage | 1.8V / 3.3V |
| Oscillator Type | Internal |
| Core Revision | ARM Cortex-M3 revision 2.0 |
| Instruction Set | Thumb-2 |
| SysTick Counter | 24-bit |
| Interrupt Controller | Nested Vector Interrupt Controller (NVIC) |
| Package / Case | 64-LQFP (10x10 mm) |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C |
| Packaging | Tray |
| Series | SAM3N |
| Pin Compatibility | Pin-to-pin compatible with SAM3S series |
ATSAM3N2BA-AU Pin Configuration
| Pin 1 | PB4 — General-purpose I/O port B, pin 4 (multiplexed peripheral functions per datasheet) |
| Pin 2 | PB5 — General-purpose I/O port B, pin 5 |
| Pin 3 | PB6 — General-purpose I/O port B, pin 6 |
| Pin 4 | PB7 — General-purpose I/O port B, pin 7 |
| Pin 5 | PB8 — General-purpose I/O port B, pin 8 |
| Pin 6 | PB9 — General-purpose I/O port B, pin 9 |
| Pin 7 | PB10 — General-purpose I/O port B, pin 10 |
| Pin 8 | PB11 — General-purpose I/O port B, pin 11 |
| Pin 9 | PB12 — General-purpose I/O port B, pin 12 |
| Pin 10 | PB13 — General-purpose I/O port B, pin 13 |
| Pin 11 | PB0 — General-purpose I/O port B, pin 0 |
| Pin 12 | PB1 — General-purpose I/O port B, pin 1 |
| Pin 13 | PB2 — General-purpose I/O port B, pin 2 |
| Pin 14 | PB3 — General-purpose I/O port B, pin 3 |
| Pin 15 | VDDIO — I/O supply voltage |
| Pin 16 | GND — Ground |
| Pin 17 | PA0 — General-purpose I/O port A, pin 0 |
| Pin 18 | PA1 — General-purpose I/O port A, pin 1 |
| Pin 19 | PA2 — General-purpose I/O port A, pin 2 |
| Pin 20 | PA3 — General-purpose I/O port A, pin 3 |
| Pin 21 | PA4 — General-purpose I/O port A, pin 4 |
| Pin 22 | PA5 — General-purpose I/O port A, pin 5 |
| Pin 23 | PA6 — General-purpose I/O port A, pin 6 |
| Pin 24 | PA7 — General-purpose I/O port A, pin 7 |
| Pin 25 | PA8 — General-purpose I/O port A, pin 8 |
| Pin 26 | PA9 — General-purpose I/O port A, pin 9 |
| Pin 27 | PA10 — General-purpose I/O port A, pin 10 |
| Pin 28 | PA11 — General-purpose I/O port A, pin 11 |
| Pin 29 | VDDCORE — Core supply voltage (1.8V domain) |
| Pin 30 | GND — Ground |
| Pin 31 | PA12 — General-purpose I/O port A, pin 12 |
| Pin 32 | PA13 — General-purpose I/O port A, pin 13 |
| Pin 33 | PA14 — General-purpose I/O port A, pin 14 |
| Pin 34 | PA15 — General-purpose I/O port A, pin 15 |
| Pin 35 | PA16 — General-purpose I/O port A, pin 16 |
| Pin 36 | PA17 — General-purpose I/O port A, pin 17 |
| Pin 37 | PA18 — General-purpose I/O port A, pin 18 |
| Pin 38 | PA19 — General-purpose I/O port A, pin 19 |
| Pin 39 | PA20 — General-purpose I/O port A, pin 20 |
| Pin 40 | PA21 — General-purpose I/O port A, pin 21 |
| Pin 41 | VDDIO — I/O supply voltage |
| Pin 42 | GND — Ground |
| Pin 43 | PA22 — General-purpose I/O port A, pin 22 |
| Pin 44 | PA23 — General-purpose I/O port A, pin 23 |
| Pin 45 | PA24 — General-purpose I/O port A, pin 24 |
| Pin 46 | PA25 — General-purpose I/O port A, pin 25 |
| Pin 47 | PA26 — General-purpose I/O port A, pin 26 |
| Pin 48 | PA27 — General-purpose I/O port A, pin 27 (multiplexed with XIN - crystal input) |
| Pin 49 | PA28 — General-purpose I/O port A, pin 28 (multiplexed with XOUT - crystal output) |
| Pin 50 | PA29 — General-purpose I/O port A, pin 29 |
| Pin 51 | PA30 — General-purpose I/O port A, pin 30 |
| Pin 52 | PA31 — General-purpose I/O port A, pin 31 |
| Pin 53 | NRST — Bidirectional reset pin (open-drain, internal pull-up) |
| Pin 54 | VDDPLL — PLL supply voltage |
| Pin 55 | GND — Ground |
| Pin 56 | VDDCORE — Core supply voltage |
| Pin 57 | VDDIN — Voltage regulator input supply |
| Pin 58 | VDDOUT — Voltage regulator output (core 1.8V, decouple to GND) |
| Pin 59 | GND — Ground |
| Pin 60 | PA0/TEST — Test mode pin (per datasheet; tie per datasheet guidance in production) |
| Pin 61 | PB0/ERASE — Flash erase pin (per datasheet; tie per datasheet guidance in production) |
| Pin 62 | VDDIO — I/O supply voltage |
| Pin 63 | GND — Ground |
| Pin 64 | VDDFLASH — Flash supply voltage |
Typical Applications
ATSAM3N2BA-AU is suitable for 6 applications: Industrial Automation Nodes, Cost-Sensitive Consumer Electronics, Medical Device Control Boards, Embedded Communication Gateways, Test and Measurement Instrumentation, Battery-Powered Portable Devices.
Industrial Automation Nodes
The ATSAM3N2BA-AU fits industrial automation nodes such as sensor hubs, motor-control front ends, and Modbus/RS-485 communication endpoints because its 48 MHz ARM Cortex-M3 delivers enough headroom for protocol stacks while the 128KB Flash and 16KB SRAM keep the BOM economical at high volumes. With 47 GPIO lines, it directly drives relays, optocoupler inputs, and LED status clusters without port expanders. Running from a 3.3V rail with an internal oscillator option, it tolerates reduced external component counts typical of industrial control boards, and the -40C to +85C temperature range covers cabinet and factory-floor environments. Firmware written on pin-compatible SAM3S boards migrates without PCB respin, protecting long-lifecycle industrial product roadmaps.
Recommended
Cost-Sensitive Consumer Electronics
For high-volume consumer products - small appliance controllers, charger accessories, toy electronics, and remote controls - the ATSAM3N2BA-AU's aggressive price point is the datasheet's stated reason for existence: the SAM3N series was designed specifically as the reduced-BOM-cost member of the SAM3 family. The 48 MHz Cortex-M3 provides responsive user-interface handling (capacitive buttons, OLED refresh) that 8-bit MCUs struggle with, while the internal oscillator removes the cost of an external crystal in non-timing-critical products. The 64-LQFP 10x10 mm footprint is hand-solderable for prototyping and standard for Asian contract-manufacturing lines, and Tray packaging suits pick-and-place assembly in large production runs.
Recommended
Medical Device Control Boards
Benchtop medical accessories, patient-monitoring peripherals, and diagnostic instrument sub-boards benefit from the ATSAM3N2BA-AU's deterministic Cortex-M3 interrupt architecture (NVIC) and 32-bit arithmetic for filtering and scaling sensor data. The -40C to +85C operating range and 3.3V I/O simplify integration with analog front ends and isolation circuitry. With 128KB Flash, the device holds acquisition routines plus communication firmware (USB CDC or UART-based links), and the 24-bit SysTick timer supports precise sampling scheduling. Because the SAM3N family is pin-to-pin compatible with SAM3S, regulated medical product families can qualify one PCB and populate either series depending on the certification tier and peripheral requirements of each SKU.
Recommended
Embedded Communication Gateways
Serial-to-serial bridges, CAN/RS-485 protocol translators, and IoT edge nodes use the ATSAM3N2BA-AU where a full 32-bit MPU is overkill but 8-bit MCUs lack throughput. The 48 MHz Cortex-M3 with Thumb-2 code density handles buffer management and CRC/checksum computation efficiently within 16KB SRAM, and 47 I/O lines accommodate dual UARTs, status indication, and configuration DIP inputs simultaneously. The internal oscillator supports field deployments where a crystal is an unnecessary failure point for UART-speed communication. Firmware images for OTA-updatable devices fit comfortably in the 128KB Flash with a dual-bank or bootloader-plus-application partitioning strategy, an important consideration for remotely deployed gateways.
Recommended
Test and Measurement Instrumentation
Portable meters, data loggers, and bench-instrument front panels use the ATSAM3N2BA-AU for its balanced mix of processing throughput and low system cost. The Cortex-M3's hardware divide and 32-bit math accelerate calibration-curve computation, while the NVIC delivers deterministic timer-interrupt latency for periodic ADC sampling scheduling via the 24-bit SysTick. 128KB Flash stores multilingual display strings, calibration tables, and USB-serial firmware concurrently. Battery-powered instruments benefit from the 1.8V/3.3V supply flexibility and clock gating of unused peripherals between samples. Pin compatibility across the SAM3N/SAM3S 64-LQFP family lets instrument OEMs reuse one layout across entry, mid, and premium models with only BOM changes.
Recommended
Battery-Powered Portable Devices
Handheld devices, portable readers, and wireless accessory units leverage the ATSAM3N2BA-AU's 1.8V/3.3V supply operation and internal oscillator to simplify low-power power trees. Designers gate clocks to unused peripherals between wake events and rely on the Cortex-M3 sleep modes to stretch battery life; the 48 MHz core wakes quickly to burst-process data, then returns to low-power idle. The 47 GPIO lines drive keypads, e-ink or segment LCD interfaces, and LED indicators without external logic. Because no external crystal is mandatory, the PCB stays small and two-sided assembly remains feasible for compact enclosures. Firmware fits in 128KB Flash with room for a bootloader enabling field updates over the device's serial link.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM3N2BA-AU — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3N1BA-AU | ATSAM3N4BA-AU | ATSAM3S2BA-AU | ATSAM3S4BA-AU |
|---|---|---|---|---|---|
| Package | 64-LQFP (10x10 mm) | 64-LQFP (10x10 mm) - same | 64-LQFP (10x10 mm) - same | 64-LQFP (10x10 mm) - same | 64-LQFP (10x10 mm) - same |
| Brand | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) |
| Core / Max Speed | ARM Cortex-M3, 48 MHz | ARM Cortex-M3, 48 MHz | ARM Cortex-M3, 48 MHz | ARM Cortex-M3, 48 MHz | ARM Cortex-M3, 48 MHz |
| Flash Memory | 128KB (128K x 8) | 64KB | 256KB | 128KB | 256KB |
| Number of I/O | 47 | 47 | 47 | 47 (pin-to-pin compatible per datasheet) | 47 (pin-to-pin compatible per datasheet) |
| Pin Compatibility with SAM3S | Yes (per Atmel datasheet) | Yes | Yes | Is the SAM3S series | Is the SAM3S series |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Supply Voltage | 1.8V / 3.3V | 1.8V / 3.3V | 1.8V / 3.3V | 1.8V / 3.3V | 1.8V / 3.3V |
Key Differentiators
- Pin-to-pin compatibility with SAM3S series (vs ATSAM3S2BA-AU)
- Lower cost per Flash KB than larger variants (vs ATSAM3N4BA-AU)
- Balanced memory at the same price class (vs ATSAM3N1BA-AU)
Design Notes
The SAM3N uses separate supply domains: VDDIO for I/O (3.3V typical), VDDCORE/VDDOUT for the internal 1.8V core supplied by the on-chip regulator from VDDIN, and VDDPLL for the PLL. Decouple VDDOUT with the capacitance specified in the datasheet electrical characteristics table (typically a few uF plus 100nF ceramic) and never drive VDDOUT from an external 1.8V source while the internal regulator is active. Power up VDDIO and VDDIN together to avoid latch-up on I/O rings.
Use the 64-LQFP 10x10 mm footprint standard land pattern with a solid ground plane on layer 2. Place 100nF ceramic decoupling capacitors within 2 mm of each VDDIO/VDDCORE pin pair, sharing one via to ground per capacitor. Keep the NRST trace short and route it away from switching signals; the internal pull-up is weak, so an external 10k pull-up plus 100nF to ground improves reset integrity in noisy industrial environments. The ERASE and TEST pins must be tied per datasheet guidance, not left floating.
The internal oscillator removes the crystal requirement for UART-class timing but is not accurate enough for USB or precise long-term timekeeping - add a crystal on XIN/XOUT (PA27/PA28 region) when the application needs it. Verify Flash and SRAM budget early: 128KB Flash and 16KB SRAM fill up quickly with a USB stack plus display firmware; if you exceed ~80% utilization, migrate to the pin-compatible ATSAM3N4BA-AU (256KB Flash, 24KB SRAM) rather than squeezing the same footprint.
Compliance Information
Compliance data was not present in the verified web data provided. The -AU suffix in Atmel/Microchip part numbering conventionally indicates a lead-free/RoHS package, but per data authenticity rules this must be confirmed on the official Microchip product page before publication.