ATSAM3N1BB-AU - 48MHz Cortex-M3 MCU 64KB Flash | Microchip
MPN: ATSAM3N1BB-AU ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.13 | $4.13 |
| 10 | $3.92 | $39.20 |
| 100 | $3.55 | $355.00 |
| 500 | $3.25 | $1,625.00 |
| 1,000 | $2.95 | $2,950.00 |
ATSAM3N1BB-AU Overview
A microcontroller unit (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: MCU -> embedded processor -> application processor. The SAM3N family belongs to Microchip's (formerly Atmel's) ARM-based Flash MCU portfolio and sits in the cost-optimized, high-volume segment of that hierarchy, targeting applications that need 32-bit performance without the cost of higher-integration parts.
Key features of the ATSAM3N1BB include the ARM Cortex-M3 revision 2.0 core running at up to 48 MHz, Thumb-2 instruction set support, a 24-bit SysTick counter, and a Nested Vector Interrupt Controller (NVIC). According to Microchip documentation, the SAM3N series offers up to 256KB Flash and up to 24KB SRAM across family variants, with the SAM3N1B specifically providing 64KB Flash. The green (Grn) LQFP package is RoHS-oriented for lead-free assembly.
The most strategically important feature is pin compatibility: the SAM3N series is pin-to-pin compatible with the SAM7S legacy products (48- and 64-pin versions) and the SAM3S series (48-, 64-pin versions), which facilitates migration within the family and protects PCB investments across design generations.
Typical applications include cost-sensitive industrial control boards, consumer appliances, metering front ends, and high-volume embedded systems where aggressive pricing and ARM ecosystem tooling matter more than maximum integration.
Design consideration: choose the 64-pin LQFP variant only if you need the expanded I/O; the family also offers 48-pin options for lower-cost boards, and code is portable across the family via the CMSIS-compatible toolchain (Atmel/Microchip Studio, ARM GCC).
This page synthesizes distributor pricing, pin-compatible SAM3N/SAM3S/SAM7S alternatives, and practical migration notes not consolidated on the manufacturer datasheet page.
Drop-in alternatives for ATSAM3N1BB-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 ATSAM3N1BB-AU (same form factor and footprint) — differing in Package, Core Processor, Core Size, Flash Memory, Maximum Clock Frequency.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAM3N1AB-AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$3.98 / Unit
View Datasheet →ATSAM3S1CB-AU
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$3.1 / Unit
View Datasheet →ATSAM3N1BB-AU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M3 (revision 2.0) |
| Core Size | 32-bit |
| Maximum Clock Frequency | 48 MHz |
| Flash Memory | 64KB (64K x 8) |
| Instruction Set | Thumb-2 |
| Interrupt Controller | NVIC (Nested Vector Interrupt Controller) |
| SysTick Timer | 24-bit |
| Package | 64-LQFP (10 x 10 mm) |
| Mounting Type | Surface Mount |
| Series | SAM3N |
| Package Green Status | Grn (green/lead-free per Utmel listing) |
| Pin Compatibility | Pin-to-pin compatible with SAM7S (48/64-pin) and SAM3S (48/64-pin) |
ATSAM3N1BB-AU grn (green/lead-free per utmel listing) Pin Configuration Guide
Pin configuration for ATSAM3N1BB-AU (grn (green/lead-free per utmel listing) 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 ATSAM3N1BB-AU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM3N1BB-AU is suitable for 6 applications: Industrial Control Boards, Metering and Smart Energy Front Ends, Consumer Appliances, Legacy SAM7S Design Upgrades, Building Automation and Sensor Nodes, Cost-Optimized Embedded Prototyping and Education.
Industrial Control Boards
The ATSAM3N1BB-AU fits industrial control boards because its 48 MHz ARM Cortex-M3 core provides deterministic, interrupt-driven control-loop performance, while the NVIC ensures low, bounded interrupt latency for time-critical I/O such as relay actuation and sensor polling. The 64KB Flash accommodates a full control application with communication stacks, and the Thumb-2 instruction set keeps the binary compact within that budget. Its 64-pin LQFP exposes ample GPIO for driving indicators, reading switches, and interfacing USART/SPI/TWI peripherals to PLC-style I/O modules. Microchip positions the SAM3N series for cost-sensitive, high-volume applications, and the aggressive price point makes it economical even in nodes deployed by the tens of thousands. Pin compatibility with SAM3S also gives industrial OEMs a forward migration path if USB or more Flash is needed later.
Recommended
Metering and Smart Energy Front Ends
Energy meters and sub-metering nodes benefit from the ATSAM3N1BB-AU's combination of 32-bit arithmetic throughput and low component cost. The Cortex-M3 core at 48 MHz performs fixed-point accumulation and scaling of pulse or serial meter data efficiently, while the 24-bit SysTick provides a stable timebase for interval billing counters. The 64KB Flash stores calibration tables and communication firmware, and the 64-pin LQFP provides enough GPIO and serial interfaces (USART, SPI, TWI) to talk to metrology ADCs and isolation interfaces. Because metering programs are deployed in very high volumes and run for years, the SAM3N family's migration path - pin-to-pin compatible with SAM7S and SAM3S - protects the PCB investment across MCU generations, reducing requalification effort when supply or feature requirements change.
Recommended
Consumer Appliances
White goods, small appliances, and HVAC controllers are classic SAM3N targets: Microchip explicitly extends the series' scope 'far into cost-sensitive, high-volume applications.' The ATSAM3N1BB-AU's 48 MHz Cortex-M3 handles UI scanning, motor-control sequencing, and sensor fusion with headroom, and the 64KB Flash covers menu logic, fault logging, and serial communication protocols. The 64-pin LQFP (10 x 10 mm) is large enough for hand inspection and rework on appliance production lines, unlike fine-pitch BGA alternatives, supporting simpler test and repair strategies. The green, lead-free LQFP package meets the RoHS-oriented assembly requirements of consumer manufacturing. Where a design later needs USB (e.g., service interfaces), the pin-compatible SAM3S 64-pin variant drops onto the same PCB with no layout change.
Recommended
Legacy SAM7S Design Upgrades
Designers maintaining products originally built on Atmel SAM7S ARM7TDMI microcontrollers can drop the ATSAM3N1BB-AU onto the existing 64-pin PCB, because Microchip documents the SAM3N series as pin-to-pin compatible with SAM7S legacy products in 48- and 64-pin versions. The upgrade moves the product from an aging ARM7 core to the modern Cortex-M3 with Thumb-2 code density, an NVIC, and continued software toolchain support from Microchip (Atmel Studio heritage, ARM GCC, CMSIS). Firmware requires clock-tree and peripheral-driver adjustments, but the board, connectors, and certification-enveloped hardware remain untouched, dramatically reducing requalification cost. For obsolescence-driven lifecycle programs, the SAM3N family is the manufacturer-sanctioned migration destination, and the same footprint also accepts SAM3S parts if future features demand them.
Recommended
Building Automation and Sensor Nodes
Wall-mounted controllers, damper actuators, and networked sensor nodes use the ATSAM3N1BB-AU for its balance of processing power and price. The 48 MHz Cortex-M3 runs protocol stacks over USART, SPI, or TWI to interface with RS-485 transceivers or sensor front ends, while the 64KB Flash retains configuration data and firmware-in-the-field update capacity. The NVIC's prioritized interrupts keep button responsiveness and communication timing deterministic even under sensor-scan load. The 10 x 10 mm 64-LQFP offers enough I/O for LEDs, relays, and keypad matrices in a compact node, and the surface-mount green package suits standard SMT assembly. With eight distributors carrying the part per Octopart and deep stock reported, sourcing risk for multi-year building programs is manageable through authorized channels.
Recommended
Cost-Optimized Embedded Prototyping and Education
The ATSAM3N1BB-AU is an excellent vehicle for teaching and prototyping 32-bit ARM development on a budget. The Cortex-M3 core with Thumb-2, SysTick, and NVIC exposes all the standard ARM architectural concepts, and 64KB Flash is large enough for RTOS-based exercises yet small enough to teach careful resource budgeting. Microchip supports the SAM3N family with software libraries, project examples, and development tools, which per the manufacturer shorten the development cycle - valuable in classroom and prototyping contexts. The 10 x 10 mm LQFP-64 is solderable with hot-plate or reflow methods on hobbyist boards, and pin compatibility with SAM7S/SAM3S lets a single prototype PCB explore multiple family members by swapping the MCU, making it a practical platform for comparative embedded-systems education.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM3N1BB-AU — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3N1AB-AU | ATSAM3S1CB-AU | STR755FR1T6 |
|---|---|---|---|---|
| Brand | Microchip Technology (Atmel) | Microchip Technology | Microchip Technology | STMicroelectronics |
| Core | ARM Cortex-M3 | ARM Cortex-M3 | ARM Cortex-M3 | ARM7TDMI |
| Pin Compatibility with Target | - | Pin-to-pin (64-pin SAM3N family) | Pin-to-pin (SAM3S/SAM3N 64-pin, per Microchip) | Cross-reference only - not verified pin-to-pin |
Key Differentiators
- 64KB Flash in the smallest SAM3N 64-pin footprint at aggressive pricing (vs ATSAM3N1AB-AU)
- Forward migration path with USB capability (vs ATSAM3S1CB-AU)
- Modern Cortex-M3 core vs legacy cross-brand substitutes (vs STR755FR1T6)
Design Notes
When migrating a SAM7S design to the ATSAM3N1BB-AU, do not assume firmware portability beyond the pinout. The ARM7TDMI-to-Cortex-M3 transition changes the interrupt architecture (NVIC vector table), flash wait-state tuning, and clock-tree registers. Budget firmware rework for the system initialization and interrupt handlers even though the PCB is unchanged. Estimate: most projects spend the majority of migration effort in the clock configuration and peripheral driver layers, not in application logic, because Thumb-2 application code ports with minimal change.
The 64-pin LQFP (10 x 10 mm, 0.5 mm pitch) requires standard fine-pitch layout practice: maintain solder-mask-defined pads per the Microchip LQFP land-pattern recommendation, and use a thermal relief-friendly ground plane for the exposed package. Decouple each supply pin group with 100 nF ceramics placed within 2-3 mm of the pins, and add bulk capacitance near the regulator. Because SAM3N 64-pin parts are footprint-compatible with SAM3S 64-pin parts, design the land pattern from the shared family drawing so a future drop-in upgrade needs no PCB respin.
Cross-reference databases list non-Microchip parts (e.g., STR755FR1T6, LPC11E68JBD64) as 'alternatives' for this MPN, but these are parametric substitutes only - they are not pin-to-pin drop-ins and will not solder onto the same land pattern. Cross-reference data also flags a counterfeit risk (approximately 65% fake threat level in the open market) for this popular part. Source exclusively from franchised distributors (DigiKey, Mouser) and require certificates of conformance for production buys.
Compliance Information
Utmel listing describes the package as 'LQFP, Grn' - Microchip's 'Green' designation indicates lead-free (and typically halogen-free) construction; formal RoHS/REACH declarations should be obtained from Microchip's product page per date code. Not an automotive AEC-Q100 part per available data.
