ATSAM3N4BA-AU - 48MHz Cortex-M3, 256KB Flash MCU | Microchip
MPN: ATSAM3N4BA-AU β Active| Qty | Unit Price | Extended |
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| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
ATSAM3N4BA-AU Overview
A microcontroller unit (MCU) is a single-chip computer that integrates a processor core, non-volatile program memory, RAM, and peripheral functions such as timers, serial interfaces, and analog-to-digital converters. Within the embedded-systems hierarchy, the ATSAM3N4BA sits in the general-purpose 32-bit MCU class, one step above 8-bit controllers like the PIC16 family and one step below high-performance application processors, making it well suited for cost-sensitive control tasks that still require 32-bit arithmetic and C-friendly execution.
Key features include the ARM Cortex-M3 revision 2.0 core executing Thumb-2 instructions, a 24-bit SysTick timer, a nested vector interrupt controller (NVIC), and an internal oscillator that removes the need for an external crystal in many designs. The device operates from a single 1.62 V to 3.6 V supply (nominally 1.8 V or 3.3 V) and is characterized for industrial temperature ranges. The B-suffix SAM3N variant adds peripheral connectivity such as HSMCI for SD/MMC media storage alongside USART, SPI, TWI, and PWM channels.
Architecturally, the SAM3N series uses the Cortex-M3 three-stage pipeline with Harvard bus structure, delivering deterministic interrupt latency and efficient code density through Thumb-2. Per the SAM3N datasheet summary, the SAM3N4/2/1/0/00 series is pin-to-pin compatible with SAM3S products, which simplifies migration between memory and peripheral density points.
Typical applications include industrial sensors and control nodes, consumer appliances, metering front ends, and battery-powered portable equipment where 48 MHz performance, 256 KB flash, and low power matter more than USB or Ethernet connectivity.
When designing with this device, verify that your codebase fits within 256 KB flash and 24 KB SRAM, and consider the SAM3S series if USB device capability is needed, since footprints are shared.
This page synthesizes distributor availability data, drop-in alternatives within the SAM3N/SAM3S pin-compatible family, and practical design guidance not found in the manufacturer datasheet.
Drop-in alternatives for ATSAM3N4BA-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 ATSAM3N4BA-AU (same form factor and footprint) β differing in Core Processor, Interrupt Controller, Package / Case, Pin Compatibility, Series.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
No drop-in alternatives available for this product.
Request AlternativesATSAM3N4BA-AU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M3 (revision 2.0) |
| Core Size | 32-bit |
| Maximum Clock Speed | 48 MHz |
| Flash Memory | 256 KB (256K x 8) |
| SRAM | 24 KB (24K x 8) |
| Number of I/O | 47 |
| Supply Voltage | 1.8 V / 3.3 V (1.62 V to 3.6 V) |
| Oscillator Type | Internal |
| Instruction Set | Thumb-2 |
| SysTick Timer | 24-bit |
| Interrupt Controller | NVIC (Nested Vectored Interrupt Controller) |
| Package / Case | 64-LQFP (10 x 10 mm) |
| Mounting Type | Surface Mount |
| Packaging | Tray |
| Pin-to-Pin Compatibility | SAM3S series |
ATSAM3N4BA-AU 64-lqfp (10 x 10 mm) Pin Configuration Guide
Pin configuration for ATSAM3N4BA-AU (64-lqfp (10 x 10 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 ATSAM3N4BA-AU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM3N4BA-AU is suitable for 6 applications: Industrial Sensor Nodes, Data Logging with SD/MMC Storage, Metering and Building Automation, Portable and Battery-Powered Devices, Appliance and Consumer Control Boards, Motor Control and Actuation Interfaces.
Industrial Sensor Nodes
The ATSAM3N4BA-AU fits industrial sensor acquisition nodes because its 48 MHz Cortex-M3 core handles filtering and protocol conversion while 256 KB of Flash retains room for OTA-style field updates and 24 KB SRAM buffers multi-channel samples. Its internal oscillator simplifies BOM in sealed sensor housings, and 1.8 V/3.3 V operation eases integration with low-power analog front ends. Wired links such as USART, SPI, and TWI connect to fieldbus bridges or gateways, and the 47 GPIO lines drive local relays and status indicators in the same footprint.
Recommended
Data Logging with SD/MMC Storage
Because the B-suffix SAM3N4BA integrates an HSMCI controller, the device is a natural fit for dataloggers that write sensor streams to SD or MMC cards. The 48 MHz CPU sustains FAT filesystem updates while SPI-connected ADCs stream data over DMA-style buffered transfers, and the 256 KB Flash stores logging firmware plus data tables. Power budgets benefit from 3.3 V single-supply operation with internal clocking, and the pin-compatible family lets engineers move between memory densities as log capacity requirements evolve without PCB respins.
Recommended
Metering and Building Automation
Utility meters, HVAC controllers, and lighting-control panels benefit from the ATSAM3N4BA-AU's combination of 47 GPIO, multiple UART/TWI channels for communicating with metering ICs, and enough Flash headroom for communication stacks and calibration tables. The Cortex-M3's deterministic NVIC interrupt latency supports precise energy-pulse counting, while industrial temperature characterization suits unconditioned meter cabinets. The internal oscillator removes crystal-related field failures, and Thumb-2 code density keeps modest 256 KB Flash sufficient for full application, bootloader, and future feature additions.
Recommended
Portable and Battery-Powered Devices
Handheld instruments and portable peripherals use the ATSAM3N4BA-AU for its 1.62 V to 3.6 V single-supply operation and internal oscillator, which reduce component count on compact PCBs. The 48 MHz Cortex-M3 provides headroom for GUI refresh and signal processing while remaining frugal in sleep modes for battery operation. SPI and TWI interfaces connect displays, touch controllers, and battery monitors, and the 64-LQFP 10 x 10 mm footprint balances hand-assembly feasibility with routing density typical of portable product layouts.
Recommended
Appliance and Consumer Control Boards
Washing machines, small cooktops, and ventilation controls require moderate compute with robust GPIO and PWM capability - exactly the profile of the ATSAM3N4BA-AU. Its 47 I/O lines directly drive seven-segment displays, keypads, triac firing circuits, and encoder inputs, while Cortex-M3 performance at 48 MHz covers closed-loop control timing. The pin-to-pin compatibility with the SAM3S series (per the Atmel datasheet) gives appliance OEMs a USB-enabled migration path for connected product variants without changing the control-board layout or certification base.
Recommended
Motor Control and Actuation Interfaces
Small actuation systems - damper drives, pump controllers, and stepper-based mechanisms - use the ATSAM3N4BA-AU's PWM channels and precise Cortex-M3 interrupt timing to generate commutation and duty-cycle control signals. The 24-bit SysTick timer provides a stable timebase for control loops, and 47 GPIO support limit-switch sensing and H-bridge direction control. Running from a 3.3 V rail shared with gate-driver logic simplifies power-tree design, while the industrial temperature rating and internal oscillator improve reliability in electrically noisy motor enclosures.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM3N4BA-AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3S4BA-AU | ATSAM3N4AA-AU | ATSAM3N2BA-AU | ATSAM3N1BA-AU | ATSAM3S4AA-AU |
|---|---|---|---|---|---|---|
| Package | 64-LQFP (10 x 10 mm) | 64-LQFP (10 x 10 mm) - same | 64-LQFP (10 x 10 mm) - same | 64-LQFP (10 x 10 mm) - same | 64-LQFP (10 x 10 mm) - same | 64-LQFP (10 x 10 mm) - same |
| Brand | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) | Microchip Technology (Atmel) |
| Core / Clock | Cortex-M3, 48 MHz | Cortex-M3, 48 MHz | Cortex-M3, 48 MHz | Cortex-M3, 48 MHz | Cortex-M3, 48 MHz | Cortex-M3, 48 MHz |
| Flash | 256 KB | 256 KB | 256 KB | 128 KB | 64 KB | 256 KB |
| SRAM | 24 KB | 24 KB | 24 KB | 16 KB | 12 KB | 24 KB |
| USB Device Port | No | Yes | No | No | No | Yes |
| HSMCI (SD/MMC) | Yes (B-suffix) | Yes | No | Yes (B-suffix) | Yes (B-suffix) | No |
Key Differentiators
- Largest SAM3N memory density with SD/MMC interface (vs ATSAM3N2BA-AU)
- Documented SAM3S pin compatibility enables zero-respin USB upgrade (vs ATSAM3S4BA-AU)
- Honest trade-off: no USB or Ethernet connectivity (vs ATSAM3S4BA-AU)
Design Notes
Verify memory fit before layout freeze: the ATSAM3N4BA-AU provides 256 KB Flash and 24 KB SRAM, which is generous for control code but tight for large buffers or RTOS-heavy stacks. If your code image exceeds 256 KB or your SRAM budget grows, plan migration to a pin-compatible SAM3S part with larger flash (e.g., SAM3S8/SAM3S16) rather than a mid-project respin - the datasheet guarantees pin-to-pin compatibility across the SAM3N/SAM3S families.
The device operates from a single 1.62 V to 3.6 V supply with a nominal 3.3 V rail. Decouple each VDD/VDDIO pin pair with 100 nF ceramic capacitors placed within a few millimeters of the pins, plus one bulk 10 uF capacitor per power domain. Because the internal oscillator is enabled by default, a power-gated or battery design can start up without crystal settling delay - but enable the crystal path and appropriate startup time in firmware if your application needs UART-class timing accuracy.
The 64-LQFP 10 x 10 mm footprint supports straightforward two-layer routing for GPIO-rich designs: keep the 0.5 mm pitch leads fan out on the top layer, and reserve ground pours for analog rails feeding any on-chip peripherals. If a future upgrade to the USB-capable ATSAM3S4BA-AU is plausible, route the shared USB/DDM pins to a test point or small connector footprint now - this preserves the migration path documented in the SAM3N datasheet pin-compatibility statement without a PCB respin later.
Compliance Information
Compliance status was not stated in the verified web data; Microchip SAM3N standard industrial parts are typically RoHS-compliant, but confirm on the Microchip product page before procurement.
