ATSAM3N2AA-MU - 48MHz Cortex-M3 MCU 128KB Flash | Microchip
MPN: ATSAM3N2AA-MU ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.77 | $9.77 |
| 10 | $9.2 | $92.00 |
| 100 | $8.55 | $855.00 |
| 500 | $7.9 | $3,950.00 |
| 1,000 | $7.35 | $7,350.00 |
ATSAM3N2AA-MU Overview
A microcontroller (MCU) is a single integrated circuit that combines a processor core, program memory, data memory, and peripherals into one chip, forming the complete intelligence of an embedded system. Within the power-management hierarchy of embedded design, the SAM3N series sits in the cost-sensitive 32-bit MCU segment, built on the ARM Cortex-M3 RISC processor architecture and programmed with Thumb-2 instructions.
Key features include the ARM Cortex-M3 revision 2.0 core running to 48 MHz, a 24-bit SysTick counter, a nested vector interrupt controller (NVIC), and an internal oscillator that removes the need for an external crystal in many designs. The peripheral set integrates 2x USARTs, 2x UARTs, 2x TWI (I2C-compatible) interfaces, 3x SPI ports, 1 PWM timer, and 6x general-purpose timers, plus an 8-channel 10-bit ADC for analog sensing.
Technical depth: the SAM3N series is Atmel's entry point into Cortex-M3 technology, pin-to-pin compatible with the best-selling SAM7S and SAM3S series, and supports native Atmel QTouch capacitive touch (buttons, sliders, wheels). Advanced power management and low operating voltage capability (1.62V to 3.6V) reduce system power consumption.
Typical applications include industrial control boards, consumer appliances, capacitive-touch user interfaces, and cost-sensitive, high-volume embedded products where SAM3S performance is needed at reduced BOM cost.
Design consideration: choose the SAM3N over SAM3S when the reduced peripheral set of the N-series meets requirements, since it is pin-compatible and lowers cost; verify SRAM sizing for applications with large communication buffers.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATSAM3N2AA-MU — 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-MU (same form factor and footprint) — differing in Package, SRAM, Core Processor, Flash Memory, Pin Compatibility.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAM3N1AA-MU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$3.18 / Unit
View Datasheet →ATSAM3N4AA-MU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$4.1 / Unit
View Datasheet →ATSAM3N2AA-AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$2.68 / Unit
View Datasheet →ATSAM3S1AA-MU
✅ Drop-In✓ In Stock
$3.34 / Unit
View Datasheet →ATSAM3S2AA-MU
✅ Drop-In✓ In Stock
$3.6 / Unit
View Datasheet →ATSAM3S4AA-MU
✅ Drop-In✓ In Stock
$3.85 / Unit
View Datasheet →ATSAM3N2AA-MU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M3 revision 2.0 |
| Core Size | 32-bit |
| Maximum Clock Speed | 48 MHz |
| Flash Memory | 128 KB (128K x 8) |
| SRAM | 16 KB (16K x 8) |
| Number of I/O | 34 |
| Supply Voltage Range | 1.62 V to 3.6 V |
| USART Peripherals | 2 |
| UART Peripherals | 2 |
| SPI Peripherals | 3 |
| TWI (I2C) Peripherals | 2 |
| PWM Channels | 1 PWM timer |
| General-Purpose Timers | 6 |
| ADC Resolution | 10-bit, 8 channels |
| Oscillator Type | Internal |
| Touch Support | Atmel QTouch capacitive touch (buttons/sliders/wheels) |
| Package | 48-QFN (7x7 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (TR) |
| Instruction Set | Thumb-2 |
| Pin Compatibility | SAM7S and SAM3S series (48-pin versions) |
ATSAM3N2AA-MU 48-qfn (7x7 mm) with exposed pad Pin Configuration Guide
Pin configuration for ATSAM3N2AA-MU (48-qfn (7x7 mm) with exposed pad 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-MU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM3N2AA-MU is suitable for 6 applications: Industrial Control Boards, Capacitive Touch User Interfaces, Cost-Sensitive High-Volume Consumer Products, Sensor Acquisition and Data Logging, Migration from SAM7S Legacy Designs, Embedded Communication Nodes.
Industrial Control Boards
The ATSAM3N2AA-MU fits industrial control applications that need 32-bit processing at an aggressive price point. Its 48 MHz Cortex-M3 core executes control loops with Thumb-2 efficiency, while six general-purpose timers and one PWM timer handle motor control, PWM outputs, and event timing. The 8-channel 10-bit ADC digitizes sensor inputs such as temperature and current feedback, and the 2x USART, 2x UART, 3x SPI, and 2x TWI interfaces connect PLC-style peripherals, displays, and field communications. With 128 KB Flash and 16 KB SRAM, it supports bare-metal or RTOS firmware, and the 1.62V to 3.6V supply range simplifies power-tree design on 3.3V industrial boards. Pin compatibility with the SAM3S series gives designers a low-risk upgrade path if more peripherals are needed later.
Recommended
Capacitive Touch User Interfaces
The SAM3N series provides native Atmel QTouch capacitive touch support for buttons, sliders, and wheels, making the ATSAM3N2AA-MU a strong fit for appliance panels and HMI boards. QTouch is implemented via firmware libraries on the 48 MHz Cortex-M3 core, eliminating an external touch controller and reducing BOM cost - a core design goal of the SAM3N series. The 34 GPIO lines drive LEDs, backlight, and relays around the touch surface, while USART and TWI interfaces report touch events to a host controller. The internal oscillator reduces component count, and the 128 KB Flash provides ample room for the QTouch library plus application firmware. For higher channel counts or larger flash needs, the pin-compatible ATSAM3N4AA-MU drops onto the same 48-QFN footprint.
Recommended
Cost-Sensitive High-Volume Consumer Products
Atmel positions the SAM3N series as its entry point into Cortex-M3 technology, specifically targeting cost-sensitive, high-volume applications - the classic domain of small appliances, toys, chargers, and white-goods sub-boards. The ATSAM3N2AA-MU delivers 48 MHz 32-bit performance, 128 KB Flash, and 16 KB SRAM at a price point below the SAM3S equivalents, and its pin-to-pin compatibility with SAM3S and SAM7S lets one PCB design span multiple cost/performance tiers by swapping MPNs. The internal oscillator removes the crystal from the BOM, and the low 1.62V to 3.6V operating range enables battery-powered designs. Tape-and-reel packaging (standard quantity 3000+ units) supports automated high-volume SMT assembly.
Recommended
Sensor Acquisition and Data Logging
With an 8-channel 10-bit ADC, six general-purpose timers, and a 24-bit SysTick counter, the ATSAM3N2AA-MU is well suited for multi-channel sensor acquisition nodes. Multiple SPI and TWI interfaces allow simultaneous connection of digital sensors (accelerometers, pressure sensors, EEPROM) while the internal ADC reads analog channels such as thermistors and voltage dividers. The 2x USARTs support RS-232/RS-485 links for uploading logged data, and 16 KB SRAM buffers sensor samples between communication windows. Low operating voltage capability (1.62V) plus advanced power management extends battery life in portable loggers. Designers should budget SRAM carefully; if logging buffers exceed 16 KB, the pin-compatible ATSAM3N4AA-MU with 24 KB SRAM is a no-redesign upgrade.
Recommended
Migration from SAM7S Legacy Designs
The ATSAM3N2AA-MU is pin-to-pin compatible with the best-selling Atmel SAM7S series in 48-pin versions, per the official datasheet, making it the recommended migration target for aging SAM7S (ARM7TDMI) designs. Moving to the SAM3N2AA-MU upgrades the core from ARM7 to a 48 MHz Cortex-M3 with Thumb-2 code density and an NVIC, typically improving performance per MHz and simplifying interrupt handling. Since the pinout is unchanged, existing PCBs can often be reused with only firmware porting and supply verification (1.62V to 3.6V). Atmel explicitly describes the SAM3N as the ideal migration path from the SAM3S for reduced BOM cost, and the same drop-in logic applies to SAM7S legacy sockets at end-of-life.
Recommended
Embedded Communication Nodes
The ATSAM3N2AA-MU integrates 2x USARTs, 2x UARTs, 3x SPI ports, and 2x TWI interfaces - an unusually rich serial set for a 48-pin cost-optimized MCU. This makes it effective as a protocol-conversion and communication node: one USART can run RS-485 Modbus while another handles a debug console, SPI ports connect Ethernet-assist peripherals or flash, and TWI manages RTCs and sensors. The 48 MHz Cortex-M3 core comfortably services interrupt-driven serial stacks within 16 KB SRAM for simple protocols. High-speed serial delivery (SPI, UART) is cited by Atmel as a key SAM3N feature. For nodes needing more RAM for stacked protocols, the pin-compatible ATSAM3N4AA-MU upgrades memory without board changes.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM3N2AA-MU — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3N1AA-MU | ATSAM3N4AA-MU | ATSAM3S2AA-MU | ATSAM3S4AA-MU |
|---|---|---|---|---|---|
| Package | 48-QFN (7x7 mm) exposed pad | 48-QFN (7x7 mm) - same | 48-QFN (7x7 mm) - same | 48-QFN (7x7 mm) - same | 48-QFN (7x7 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 | 128 KB | 64 KB | 256 KB | 128 KB | 256 KB |
| Supply Voltage | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V | 1.62 V to 3.6 V |
| Peripheral Set | 2 USART / 2 UART / 3 SPI / 2 TWI, 10-bit ADC | Same SAM3N peripheral set | Same SAM3N peripheral set | Enhanced SAM3S set (faster ADC, extra analog) | Enhanced SAM3S set (faster ADC, extra analog) |
| QTouch Support | Yes (native QTouch) | Yes (native QTouch) | Yes (native QTouch) | Yes (native QTouch) | Yes (native QTouch) |
Key Differentiators
- Lowest BOM cost within the pin-compatible family (vs ATSAM3S2AA-MU)
- Scalable memory on the same footprint (vs ATSAM3N4AA-MU)
- Legacy migration path from SAM7S (vs SAM7S 48-pin parts)
- Trade-off: fewer analog/serial features than SAM3S (vs ATSAM3S4AA-MU)
Design Notes
Design the supply rail for 1.62V to 3.6V operation; 3.3V is the typical industrial rail and 1.8V suits battery designs. Decouple each VDD/VDDIO pin with 100 nF ceramic capacitors placed within 2 mm of the pin, plus one bulk 4.7 uF to 10 uF capacitor near the device. The 48-QFN exposed pad should be soldered to a grounded thermal pad on the PCB for both heat dissipation and ground return. Verify the ADC reference configuration matches the chosen VDD rail for accurate 10-bit conversions.
The 48-QFN (7x7 mm) package with exposed pad requires a matched land pattern with the center thermal via array (typically 4-9 vias) connected to the ground plane to ensure reliable soldering and low thermal resistance. Keep crystal (if used) traces short and place load capacitors close to the OSC pins; when running on the internal oscillator, keep high-current switching traces away from the device to reduce jitter. Follow the Atmel SAM3N hardware design guidelines in the datasheet for SWD programming header placement.
A common pitfall is confusing package suffixes: -MU is the 48-QFN (7x7), while -AU is 48-LQFP - they are not footprint-interchangeable despite the same die. Another pitfall is underestimating 16 KB SRAM; communication stacks (USB CDC, TCP/IP) can exhaust it quickly - budget statically with a linker map. Flash programming voltage and lock bits differ from legacy SAM7S parts, so update flash programming scripts when migrating. Finally, verify QTouch channel assignment against GPIO multiplexing tables, since touch channels share pins with SPI/USART functions.
Compliance Information
Compliance status not stated in the retrieved web data; verify on the official Microchip product page or datasheet.