ATSAM3S4BA-MUR - 64MHz Cortex-M3 MCU 256KB Flash | Microchip
MPN: ATSAM3S4BA-MUR ✓ 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 |
ATSAM3S4BA-MUR Overview
A microcontroller (MCU) is a single integrated circuit that combines a processor core, memory, and programmable peripherals into one chip, forming the lowest layer of the embedded-systems hierarchy: microcontroller unit -> embedded processor -> semiconductor IC. The SAM3S family belongs to Microchip's (formerly Atmel) 32-bit ARM-based MCU portfolio, positioned for cost-sensitive industrial and consumer designs that need more performance than 8-bit parts without the complexity of application processors.
Key features of the ATSAM3S4BA-MUR include the 64 MHz Cortex-M3 RISC core with Thumb-2 instruction set, 256 KB (256K x 8) of on-chip Flash for code storage, 48 KB of SRAM, and operation over a wide 1.62V to 3.6V single-supply range. The device is fabricated as a green, RoHS-compliant part, supplied in Tape & Reel (the -R suffix), and rated for industrial temperature ranges.
From a technical standpoint, the Cortex-M3 core integrates a nested vectored interrupt controller (NVIC) and offers deterministic interrupt latency, while the SAM3S peripheral set includes DMA that transfers data to memory and offloads the CPU, reducing real-time burden. According to Microchip's product page, the device is pin-to-pin compatible with the SAM3N4B and SAM7S64, enabling easy migration between performance tiers on the same PCB footprint.
Typical applications include industrial control panels, consumer appliances, battery-powered metering, and USB-connected embedded devices, where 64 MHz Cortex-M3 throughput, integrated DMA, and low-power operation fit well.
A key design consideration: verify Flash size headroom, since pin-compatible SAM3N4B alternatives may offer different peripheral sets even on the same footprint.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ATSAM3S4BA-MUR — 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 ATSAM3S4BA-MUR (same form factor and footprint) — differing in RoHS Status, Packaging, Core Processor, Core Size, Maximum Clock Frequency.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ATSAM3N4BA-MU
✅ Drop-In✓ In Stock
$3.48 / Unit
View Datasheet →ATSAM3S4AA-MUR
✅ Drop-In✓ In Stock
$4.85 / Unit
View Datasheet →ATSAM3S4BA-AUR
✅ Drop-In✓ In Stock
$3.44 / Unit
View Datasheet →ATSAM3S2BA-MUR
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$4.1 / Unit
View Datasheet →ATSAM7S64CU
✅ Drop-In📋 Reference alternative (not in catalog)
ATSAM3S4BA-MUR Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M3 |
| Core Size | 32-bit |
| Maximum Clock Frequency | 64 MHz |
| Flash Memory Size | 256 KB (256K x 8) |
| SRAM Size | 48 KB |
| Supply Voltage Range | 1.62 V to 3.6 V |
| Package Type | 64-QFN (9x9 mm) with Exposed Pad |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (-R suffix) |
| Series | SAM3S |
| DMA Controller | Yes |
| Pin Compatibility | Pin-to-pin compatible with SAM3N4B and SAM7S64 (per Microchip) |
| Temperature Grade | Industrial |
| RoHS Status | Compliant |
| Halogen Status | Green package |
ATSAM3S4BA-MUR 64-qfn (9x9 mm) with exposed pad Pin Configuration Guide
Pin configuration for ATSAM3S4BA-MUR (64-qfn (9x9 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 ATSAM3S4BA-MUR.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM3S4BA-MUR is suitable for 6 applications: Industrial Control and Automation, Battery-Powered Metering, Consumer Appliances, USB-Connected Embedded Devices, Data Acquisition Systems, Legacy SAM7S64 Design Migration.
Industrial Control and Automation
The ATSAM3S4BA-MUR fits industrial control nodes because its 64 MHz ARM Cortex-M3 core provides headroom for real-time control loops while the DMA controller moves ADC and communication data without CPU intervention, as described by Microchip. Operating from a wide 1.62V to 3.6V supply simplifies integration with industrial 3.3V rails, and the industrial temperature grade suits factory-floor environments. In a typical design, the MCU runs the control firmware from 256 KB of on-chip Flash while DMA streams sensor data to the 48 KB SRAM buffer; the main trade-off versus bare 8-bit MCUs is higher unit cost, offset by superior processing throughput and deterministic Cortex-M3 interrupt handling.
Recommended
Battery-Powered Metering
Smart meters and battery-powered instrumentation benefit from the ATSAM3S4BA-MUR's combination of 256 KB Flash for protocol stacks and metering firmware with a 1.62V to 3.6V supply range that tolerates battery voltage sag. The 64 MHz Cortex-M3 processes metering algorithms quickly and returns to low-power modes, extending battery life, while the DMA controller accumulates ADC samples into the 48 KB SRAM without waking the CPU for each conversion. Designers should budget for the Cortex-M3's higher active current versus sub-1V ultra-low-power MCUs, but gain a single-chip solution that avoids external Flash and simplifies the bill of materials in compact meter enclosures.
Recommended
Consumer Appliances
White goods, small appliances, and HVAC controllers use the ATSAM3S4BA-MUR where a 32-bit MCU with substantial Flash enables touch-sensing, display driving, and communication firmware in one chip. The 64 MHz Cortex-M3 core handles simultaneous UI and control tasks; the 256 KB (256K x 8) Flash accommodates feature-rich code and over-the-air update buffers in the 48 KB SRAM. The 64-QFN (9x9 mm) package with exposed pad provides a compact, thermally robust footprint for high-volume assembly, and green RoHS-compliant construction meets consumer environmental regulations. The pin-to-pin compatibility with SAM3N4B gives appliance OEMs a documented cost-down path without PCB respins.
Recommended
USB-Connected Embedded Devices
The SAM3S series integrates USB device-class peripherals aimed at USB-connected equipment such as data loggers, programmers, and PC peripherals. The DMA controller offloads the CPU during bulk transfers, moving packet data directly to the 48 KB SRAM while the 64 MHz Cortex-M3 processes application logic, a combination Microchip highlights in the SAM3S product description. The 256 KB Flash holds USB stack plus application with room for firmware-upgrade images. Designers should verify the exact USB peripheral configuration in the SAM3S4B datasheet section for the B variant, since peripheral mixes differ across SAM3S family members sharing the same core and clock specifications.
Recommended
Data Acquisition Systems
For multi-channel data acquisition, the ATSAM3S4BA-MUR pairs its on-chip ADC peripherals with the DMA controller so conversion results stream into SRAM without per-sample CPU interrupts, directly addressing the architecture Microchip describes for the SAM3S series. The 64 MHz core then applies filtering, scaling, and protocol formatting with ample margin, while 256 KB of Flash stores calibration tables and logging firmware. The industrial temperature grade and 1.62V to 3.6V supply support rugged field installations. Compared with a separate ADC-plus-MCU solution, this single-chip approach reduces BOM count, board area, and inter-chip digital noise in the analog front end.
Recommended
Legacy SAM7S64 Design Migration
Designers maintaining legacy SAM7S64-based products can migrate to the ATSAM3S4BA-MUR without changing the PCB, because Microchip states the SAM3S4B is pin-to-pin compatible with the SAM7S64. The migration multiplies Flash from 64 KB to 256 KB and SRAM capacity, replaces the ARM7TDMI core with a 64 MHz Cortex-M3 featuring the NVIC for faster, deterministic interrupts, and modernizes the toolchain to current CMSIS-based software support. Firmware requires porting since peripheral registers differ between generations, but the identical 64-pin QFN footprint eliminates layout risk, making this a low-hardware-risk, high-software-payoff upgrade path for long-life industrial products.
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Recommended Products Summary
Engineering reference data for ATSAM3S4BA-MUR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3N4BA-MU | ATSAM3S4AA-MUR | ATSAM3S4BA-AUR | ATSAM3S2BA-MUR | ATSAM7S64CU |
|---|---|---|---|---|---|---|
| Package | 64-QFN (9x9 mm) EP | 64-QFN (9x9) - same footprint | 64-QFN (9x9) - same footprint | 64-QFN (9x9) - same footprint | 64-QFN (9x9) - same footprint | 64-QFN - same footprint |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | ARM Cortex-M3 | ARM Cortex-M3 | ARM Cortex-M3 | ARM Cortex-M3 | ARM Cortex-M3 | ARM7TDMI |
| Max Clock Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 55 MHz |
| Flash Memory | 256 KB | 256 KB | 256 KB | 256 KB | 128 KB | 64 KB |
Key Differentiators
- DMA controller offloads the CPU (vs ATSAM3N4BA-MU)
- Four times the Flash of the legacy pin-compatible part (vs ATSAM7S64CU)
- Same die at lower effective handling cost in volume (vs ATSAM3S4BA-AUR)
- Trade-off: cost versus pin-compatible SAM3N alternative (vs ATSAM3N4BA-MU)
Design Notes
Design the 3.3V rail for the full 1.62V to 3.6V operating window stated by Microchip. Decouple each VDD/VDDIO pin pair with 100 nF ceramic capacitors placed within 2 mm of the pins, plus one bulk 10 uF capacitor near the 64-QFN exposed pad. The exposed pad is the primary ground return and thermal path - connect it to a solid ground plane with a 5x5 via array. Estimated: with typical Cortex-M3 active current in the tens of mA range, IR drop on a 2-layer board is negligible, but confirm against the datasheet current-consumption tables for your clock configuration.
The 9x9 mm 64-QFN with exposed pad demands careful land-pattern design per the datasheet footprint drawing: extend pads slightly outward for paste and use solder-mask-defined or non-solder-mask-defined pads consistently. Place the 0.1 uF decoupling network on the component side directly under or beside the package. For Crystal and USB routing, keep clock traces short and guard them with ground pours. Because the part is pin-to-pin compatible with SAM3N4B and SAM7S64, a single layout can be qualified across all three, reducing future respin risk.
Do not assume all SAM3S package variants share pinout maps - peripheral multiplexing differs between the A/B/C family members even at the same Flash size, so verify the pin-multiplexing table in the SAM3S datasheet for the SAM3S4B specifically. When migrating firmware from SAM7S64, remember the Cortex-M3 NVIC vector table format differs from the ARM7TDMI vector table. Also confirm SAM3S4B-specific peripheral availability (for example DMA) in the datasheet before reusing SAM3N example code, which lacks DMA support.
Compliance Information
Distributor listings describe the part as RoHS compliant with a green (halogen-free) package. REACH and conflict-minerals declarations not stated in verified data - consult official Microchip compliance certificates.
