ATSAM3U2EA-CU - 96MHz 128KB Cortex-M3 MCU | Microchip
MPN: ATSAM3U2EA-CU ✓ ActiveATSAM3U2EA-CU Overview
A flash microcontroller is a semiconductor in which a microcontroller core, program memory, data memory, and peripherals are integrated into one package. The ATSAM3U2EA-CU sits within the hierarchy of embedded controller, 32-bit microcontroller, ARM Cortex-M processor, and SAM3U family. Its Cortex-M3 architecture provides 32-bit processing while retaining a compact embedded-control architecture suited to systems that require substantial flash memory, serial connectivity, and deterministic peripheral access without a separate external processor.
The verified features include an ARM Cortex-M3 revision 2.0 core operating to 96 MHz, a Memory Protection Unit, and the Thumb-2 instruction set. The ATSAM3U2EA-CU configuration provides 128 KB of embedded flash and 36 KB of SRAM. The SAM3U family architecture supports a 128-bit-wide flash memory interface with a memory accelerator and dual-bank organization. These characteristics make the device appropriate for USB device-class equipment, removable storage interfaces, industrial data acquisition, and connected embedded controls.
The integrated peripheral set includes a high-speed USB device port with an embedded transceiver, a high-speed memory card interface supporting SDIO, SD, and MMC, and an external bus interface. These interfaces allow a compact board to connect directly to USB hosts, flash-memory cards, and external bus peripherals. The Cortex-M3 processor and memory protection unit also support controlled execution and memory partitioning in firmware that separates application code from protected resources.
Typical uses include USB-connected data loggers, SD-card-based industrial recorders, secure access terminals, portable test equipment, and embedded control systems requiring several serial interfaces. The 96 MHz operating ceiling provides substantial throughput for protocol handling, while 128 KB of flash stores application code, boot logic, configuration data, and firmware updates. The 36 KB of SRAM supports packet buffers, working memory, and moderate real-time processing workloads.
When assigning the ATSAM3U2EA-CU, verify the complete pin-level power, ground, and peripheral assignments against the manufacturer datasheet. The 144-pin LFBGA requires a controlled PCB land pattern and careful thermal and escape-routing planning. Because the verified distributor excerpt does not provide the full electrical limits, pin names, or absolute maximum ratings, those values should not be inferred from the family-level description.
This product record combines verified distributor specifications, manufacturer datasheet availability, package information, lifecycle status, source links, and application-focused engineering guidance. It also distinguishes the target from same-package family alternatives while clearly identifying parameters that require confirmation before substitution or production release.
Drop-in alternatives for ATSAM3U2EA-CU — 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 ATSAM3U2EA-CU (same form factor and footprint) — differing in Package, Flash Memory, Memory Protection Unit, SRAM, Core Processor.
ATSAM3U4EA-CU
✅ Drop-In ⚠️ Specs UnverifiedContact for price
View Datasheet →ATSAM3U1EA-CU
✅ Drop-In ⚠️ Specs UnverifiedContact for price
View Datasheet →ATSAM3X4EA-CU
✅ Drop-InContact for price
View Datasheet →ATSAM3U2EAA-CU
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ATSAM3U2ECA-CU
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ATSAM3U2EA-CU Maximum Ratings & Electrical Characteristics
| Product Type | 32-bit ARM Cortex-M3 flash microcontroller |
| Product Series | SAM3U Series |
| Maximum CPU Frequency | 96 MHz |
| CPU Core | ARM Cortex-M3 revision 2.0 |
| Instruction Set | Thumb-2 |
| Flash Memory | 128 KB |
| SRAM | 36 KB |
| Supply Voltage | 1.8 V or 3.3 V |
| Memory Protection Unit | Yes |
| USB Interface | High-Speed USB Device Port with embedded transceiver |
| Memory Card Interface | High-Speed MCI supporting SDIO, SD, and MMC |
| External Bus | External Bus Interface |
| Package | 144-LFBGA (13 x 13 mm) |
| Pin Count | 144 pins |
| Mounting Type | Surface Mount |
| Lifecycle Status | Active |
ATSAM3U2EA-CU 144-lfbga (13 x 13 mm) Pin Configuration Guide
Pin configuration for ATSAM3U2EA-CU (144-lfbga (13 x 13 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 ATSAM3U2EA-CU.
Refer to the datasheet for full pin configuration.
Typical Applications
ATSAM3U2EA-CU is suitable for 6 applications: USB Data Logger, Industrial SD-Card Recorder, USB Secure Access Terminal, Portable Test and Measurement, Embedded Control and Automation, Removable Media and Protocol Bridge.
USB Data Logger
The ATSAM3U2EA-CU fits a USB-connected logger because its SAM3U platform combines a 96 MHz ARM Cortex-M3 core with a high-speed USB device port and embedded transceiver. The 128 KB of flash can store firmware, event descriptions, calibration information, and configuration parameters, while 36 KB of SRAM supports working buffers. A device can sample sensor data, format records internally, and present them as a USB peripheral without a separate interface controller. The principal design check is the complete package pin assignment and required USB transceiver support in the official datasheet.
Recommended
Industrial SD-Card Recorder
The ATSAM3U2EA-CU is suitable for an industrial SD-card recorder because its high-speed memory card interface supports SDIO, SD, and MMC while the Cortex-M3 core runs to 96 MHz. The 36 KB of SRAM can support file-system buffers and transaction staging, and the 128 KB of flash is available for firmware, configuration, and status information. In this architecture, the MCU can coordinate sensor acquisition, card writes, and host communication. Storage endurance, write-cycle behavior, and card compatibility must be validated at the system level because those values are not present in the supplied excerpts.
Recommended
USB Secure Access Terminal
The ATSAM3U2EA-CU can serve as the controller in a USB secure-access terminal where a 96 MHz processor handles credential parsing, command processing, status reporting, and USB device communication. Its Memory Protection Unit can support firmware architectures that separate protected and general-purpose memory regions. The 128 KB flash and 36 KB SRAM provide space for embedded code, keys, buffers, and communication state when compared with smaller microcontrollers. Designers should still perform an independent cryptographic review and verify peripheral mapping, boot behavior, and security features rather than inferring them from the core specification.
Recommended
Portable Test and Measurement
The ATSAM3U2EA-CU is appropriate for portable test equipment that combines data acquisition, USB connectivity, and removable local storage. Its 96 MHz Cortex-M3 core provides real-time processing, the 36 KB SRAM supports sample and protocol buffers, and the 128 KB flash stores measurement firmware and calibration tables. The USB device port offers a direct connection to a host computer, while the memory card interface can preserve local logs when a host is unavailable. Exact analog inputs, ADC resources, timing limits, and pin multiplexing are not included in the verified excerpts and must be checked before selecting the device.
Recommended
Embedded Control and Automation
The ATSAM3U2EA-CU can serve as the main embedded controller in an automation subsystem that needs higher arithmetic throughput and more memory than an 8-bit MCU. The 96 MHz Cortex-M3 core supports concurrent protocol handling and control tasks, the 128 KB flash accommodates application firmware, and the 36 KB SRAM provides a practical working region. Its USB and SD/MMC interfaces allow local configuration, logging, and host connectivity. For motor, safety, or high-voltage control, external drivers and protection circuitry are required; the MCU itself does not replace industrial isolation, surge protection, or functional-safety analysis.
Recommended
Removable Media and Protocol Bridge
The ATSAM3U2EA-CU can implement a protocol bridge between USB and SD, SDIO, or MMC storage because both interfaces are integrated into the SAM3U family. At up to 96 MHz, the controller can coordinate block transfers, command translation, buffering, and status feedback. Its 128 KB flash supports bridge firmware and configuration, while 36 KB of SRAM can absorb command and data traffic between the two interfaces. Verification must cover electrical levels, supported card modes, maximum transfer rates, timeout behavior, and package-level pin assignments before a board design is released.
Recommended
Recommended Products Summary
Engineering reference data for ATSAM3U2EA-CU — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ATSAM3U4EA-CU | ATSAM3U1EA-CU | ATSAM3X4EA-CU | ATSAM3U2EAA-CU | ATSAM3U2ECA-CU |
|---|---|---|---|---|---|---|
| Package | 144-LFBGA (13 x 13 mm) | 144-LFBGA (13 x 13 mm) | 144-LFBGA (13 x 13 mm) | 144-LFBGA (13 x 13 mm) | 144-LFBGA (13 x 13 mm) | 144-LFBGA (13 x 13 mm) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
Key Differentiators
- Defined 128 KB flash and 36 KB SRAM configuration (vs ATSAM3U4EA-CU)
- Directly verified USB and removable-storage integration (vs ATSAM3X4EA-CU)
- Deterministic 96 MHz Cortex-M3 processing target (vs ATSAM3U1EA-CU)
Design Notes
Treat the 144-LFBGA land pattern as a high-density escape-routing problem. Assign the ground and power pins directly from the official package drawing, preserve short return paths for USB and memory-card signals, and avoid routing high-speed signals beneath split power planes. Because the supplied source excerpts do not provide the complete pin table, the PCB footprint and escape routing must be checked against the manufacturer package drawing before release.
The device supports verified 1.8 V and 3.3 V supply options, but the exact core, I/O, and analog supply rails must be separated according to the manufacturer datasheet. Use local bulk and high-frequency decoupling on every required supply rail, keep the USB transceiver supply path compact, and verify startup sequencing. Do not assume that one external voltage can satisfy all ATSAM3U2EA-CU supply pins without checking the pin table and electrical characteristics.
Route USB D+ and D- as a controlled-impedance differential pair over a continuous reference plane, and follow the manufacturer guidance for impedance, length matching, and isolation from switching nodes. SDIO and external-bus traces also require deterministic return paths and suitable series damping where recommended. PCB stack-up, connector geometry, and peripheral clock requirements must be established before final routing; these values are not supplied in the verified excerpts.
A same-package MPN is not automatically a drop-in replacement. Before substituting any listed alternative, compare every power pin, ground pin, USB signal, memory-card signal, peripheral mapping, reset connection, programming interface, and package-ball position. Firmware may also require a different linker configuration, boot vector, clock setup, or pin-mux definition. The alternatives in this record should therefore be treated as engineering candidates requiring datasheet and software verification.
Compliance Information
The supplied manufacturer and distributor excerpts do not explicitly state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. These fields remain unknown rather than being inferred. The lifecycle status is active according to the verified Digchip specification result.
