ATSAM3SD8CA-AU - 64MHz Cortex-M3 MCU 512KB Flash | Microchip
MPN: ATSAM3SD8CA-AU β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.93 | $7.93 |
| 10 | $7.14 | $71.40 |
| 100 | $6.36 | $636.00 |
| 500 | $5.55 | $2,775.00 |
| 1,000 | $3.14 | $3,140.00 |
ATSAM3SD8CA-AU Overview
A microcontroller unit (MCU) integrates a processor core, memory, and peripherals on a single die, forming the lowest level of the embedded computing hierarchy: microcontroller -> embedded processor -> semiconductor IC. The SAM3S family belongs to the ARM Cortex-M class of 32-bit MCUs, which are widely used in industrial control, consumer devices, and IoT nodes where deterministic, low-power real-time performance is required.
Key features include the ARM Cortex-M3 revision 2.0 core with Thumb-2 instruction set, a Memory Protection Unit (MPU) for robust software partitioning, and a high-speed USB device port with an integrated transceiver, enabling fast data up/downloading and plug-and-play USB connectivity without an external PHY. Operating voltage spans 1.62V to 3.6V (1.8V/2.5V/3.3V supply systems supported).
Architecturally, the ATSAM3SD8CA-AU combines the Cortex-M3 three-stage pipeline with a rich peripheral set typical of the SAM3S series, including USARTs, SPI, TWI, ADC channels, PWM outputs, and a DMA controller. It is pin-to-pin compatible with AT91SAM7S legacy products, providing a direct migration path from Atmel ARM7 designs with higher performance and lower power consumption.
Typical applications include industrial control panels, USB data loggers, point-of-sale terminals, battery-powered metering equipment, and consumer appliances that require USB connectivity with 32-bit processing headroom. The 512KB flash accommodates complex firmware stacks such as USB device class drivers and RTOS-based designs.
A key design consideration is power management: the SAM3S offers multiple sleep and wait modes, so firmware should exploit these modes plus the dynamic clock controller to minimize average current draw in battery applications.
This page synthesizes verified distributor pricing, drop-in alternatives from the same SAM3S family, and practical design notes not found in the manufacturer datasheet, adding selection and cross-reference value beyond standard catalog listings.
Drop-in alternatives for ATSAM3SD8CA-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 ATSAM3SD8CA-AU (same form factor and footprint) β differing in Package, RoHS Status, USB.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ATSAM3S8CA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAM3S4CA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
ATSAM3S2CA-AU
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$4.25 / Unit
View Datasheet βATSAM3SD8CA-AU Maximum Ratings & Electrical Characteristics
| Core Processor | ARM Cortex-M3 revision 2.0 |
| Core Size | 32-Bit |
| Maximum Clock Frequency | 64 MHz |
| Flash Memory Size | 512KB (512K x 8) |
| Instruction Set | Thumb-2 |
| Memory Protection Unit | Yes (MPU) |
| USB | High-speed USB device with integrated transceiver |
| Operating Voltage Range | 1.62 V to 3.6 V |
| Supply Voltage Options | 1.8 V / 2.5 V / 3.3 V |
| Package | 100-LQFP (14x14 mm) |
| Pin Count | 100 |
| Mounting Type | Surface Mount |
| Compatibility | Pin-to-pin compatible with AT91SAM7S legacy (64-pin versions) and SAM3S4/2/1 products |
| Packaging | Tray |
| RoHS Status | Compliant (LQFP, Green, MRL per Mouser listing) |
ATSAM3SD8CA-AU 100-lqfp (14x14 mm) Pin Configuration Guide
Pin configuration for ATSAM3SD8CA-AU (100-lqfp (14x14 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 ATSAM3SD8CA-AU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM3SD8CA-AU is suitable for 6 applications: USB Data Loggers and Test Instruments, Industrial Control Panels, Battery-Powered Metering Equipment, Point-of-Sale Terminals, Consumer Appliances and HMI, IoT Sensor Nodes and Gateways.
USB Data Loggers and Test Instruments
The ATSAM3SD8CA-AU's high-speed USB device controller with integrated transceiver makes it a natural fit for data-logging instruments that must offload large datasets to a PC quickly. The 64 MHz Cortex-M3 core paired with DMA lets the CPU sustain USB bulk transfers while ADC channels continue sampling, and the 512KB flash stores firmware plus buffering or a small file system. Because the USB PHY is on-chip, no external transceiver is needed, reducing BOM cost and board area. Typical designs connect USB D+/D- through 22-ohm series resistors to the LQFP-100 pins with careful 90-ohm differential routing. The result is a single-chip logger with plug-and-play connectivity and fast data up/downloading.
Recommended
Industrial Control Panels
Industrial control panels benefit from the ATSAM3SD8CA-AU's combination of 32-bit real-time processing, robust EMI tolerance noted by the SAM3 family datasheet, and a rich peripheral set of USARTs, SPI, TWI, PWM, and ADC channels. The 1.62V to 3.6V operating range allows direct operation from a 3.3V industrial rail, while the MPU enables safe partitioning of application code from communication stacks. The 512KB flash accommodates protocol stacks, HMI logic, and field-updatable firmware with dual-image layouts. Its pin-to-pin compatibility with legacy AT91SAM7S parts lets panel manufacturers refresh aging ARM7 designs without a PCB respin, cutting requalification cost while gaining the faster Cortex-M3 core and Thumb-2 code density.
Recommended
Battery-Powered Metering Equipment
Utility meters and battery-powered measurement devices leverage the SAM3S low-power architecture: the dynamic clock controller and multiple sleep and wait modes let the ATSAM3SD8CA-AU spend most of its life in low-current sleep, waking to 64 MHz bursts for measurement and communication. The 1.62V minimum supply supports direct lithium-cell operation through the battery's discharge curve, and the integrated ADC handles sensor front-end duties without an external converter in cost-sensitive designs. The 512KB flash retains calibration tables and encrypted firmware images. The USB port doubles as a service interface for meter configuration during installation, using the same on-chip transceiver - so no debug-only connector is required in the final product.
Recommended
Point-of-Sale Terminals
Point-of-sale terminals require USB connectivity for peripherals and PC communication, sufficient flash for security stacks, and dependable 32-bit processing - all delivered by the ATSAM3SD8CA-AU in a single chip. The high-speed USB device port with integrated transceiver provides fast transaction and firmware-update paths, while 512KB flash hosts payment-application code, key storage routines, and dual-bank update mechanisms. The MPU supports software isolation, a common requirement in payment-security architectures. Its 100-pin LQFP offers enough GPIO for keypads, displays, and card-reader interfaces without glue logic. The part's legacy AT91SAM7S pin compatibility also allows POS vendors with older ARM7-based boards to upgrade processing without redesigning the PCB.
Recommended
Consumer Appliances and HMI
Consumer appliances with human-machine interfaces - coffee machines, HVAC controllers, white goods panels - use the ATSAM3SD8CA-AU to drive segment or graphic displays via its GPIO and PWM resources while handling capacitive-touch or encoder inputs. The 64 MHz Cortex-M3 delivers responsive UI performance, and Thumb-2 code density keeps 512KB flash ample for multi-language strings, graphics assets, and communication stacks. USB serves as a manufacturing-test and firmware-update port, exploiting the integrated transceiver for a single-chip solution. Operation from a 3.3V rail simplifies power design alongside the appliance's low-voltage electronics. The part's EMI robustness, cited in Atmel SAM3 family documentation, helps appliances pass conducted and radiated emissions testing.
Recommended
IoT Sensor Nodes and Gateways
IoT sensor nodes and edge gateways employ the ATSAM3SD8CA-AU as the local processing hub, aggregating sensor data over SPI, TWI, and USART links and forwarding it via attached radio modules. The DMA controller offloads peripheral transfers so the Cortex-M3 core can run protocol processing concurrently, and sleep modes preserve battery life in duty-cycled deployments. The 512KB flash supports TLS stacks and over-the-air update mechanisms with dual-image fallback. USB offers a convenient commissioning and diagnostics interface in the field. Because the SAM3S family spans multiple flash densities in one footprint, node variants can be cost-optimized by swapping to ATSAM3S4CA-AU or ATSAM3S2CA-AU without any PCB change.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM3SD8CA-AU β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3S8CA-AU | ATSAM3S4CA-AU | ATSAM3S2CA-AU | ATSAM3S8BA-MUR |
|---|---|---|---|---|---|
| Package | 100-LQFP (14x14 mm) | 100-LQFP (14x14 mm) - same | 100-LQFP (14x14 mm) - same | 100-LQFP (14x14 mm) - same | 100-pin BGA - different footprint |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core / Max Frequency | Cortex-M3 / 64 MHz | Cortex-M3 / 64 MHz | Cortex-M3 / 64 MHz | Cortex-M3 / 64 MHz | Cortex-M3 / 64 MHz |
| Flash Memory | 512KB | 512KB | 256KB | 128KB | 512KB |
| USB Interface | High-speed USB device, integrated transceiver | Full-speed USB device | Full-speed USB device | Full-speed USB device | Full-speed USB device |
| Operating 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 |
| Drop-in Capability | Reference part | Yes - pin-to-pin, USB speed differs | Yes - pin-to-pin, less flash | Yes - pin-to-pin, less flash | No - BGA footprint |
Key Differentiators
- High-speed USB with integrated transceiver (vs ATSAM3S8CA-AU)
- Maximum flash density in a pin-compatible footprint (vs ATSAM3S4CA-AU)
- Legacy migration compatibility (vs ATSAM3S2CA-AU)
Design Notes
For the high-speed USB interface, route D+/D- as a 90-ohm differential pair with matched lengths and place 22-ohm series resistors close to the ATSAM3SD8CA-AU pins. Although the transceiver is integrated, signal integrity still depends on short, clean routing on the 100-LQFP breakout. Follow the SAM3S datasheet USB layout guidelines and Microchip's SAM3S evaluation-board reference designs (such as the SAM3S-EK) for proven stackup and decoupling patterns.
Supply the MCU from a clean 3.3V rail within the 1.62V to 3.6V range. Decouple each VDD/VDDIO pair with 100nF ceramics placed within 2 mm of the corresponding LQFP pins, plus bulk 10uF at the board entry. Estimated: at 64 MHz active mode the SAM3S draws in the tens-of-mA class, so a low-ESR regulator such as the MCP1700 family is adequate for sleep-dominated duty cycles, but verify worst-case active current against the datasheet electrical characteristics table.
Do not confuse the ATSAM3SD8C (high-speed USB with integrated transceiver) with ATSAM3S8C (full-speed USB): they are near-equivalents but the USB peripheral differs, and firmware USB stacks are not always source-compatible between them. Also, the -AU suffix denotes the industrial temperature variant per Microchip ordering codes - confirm the suffix matches your temperature requirement when substituting within the pin-compatible SAM3S family, and always verify the flash-density code (D8 = 512KB) against your firmware size plus dual-bank OTA reserve.
Compliance Information
Mouser lists the part as LQFP, Green, IT, MRL, indicating Microchip green (RoHS/lead-free) packaging. Formal REACH and conflict-minerals statements should be requested from Microchip.