ATSAM3A4CA-AU - 84MHz Cortex-M3 MCU 256KB Flash | Microchip
料号： ATSAM3A4CA-AU ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $18.12 | $18.12 |
| 10 | $16.6 | $166.00 |
| 100 | $14.9 | $1,490.00 |
| 500 | $13.5 | $6,750.00 |
| 1,000 | $12.3 | $12,300.00 |
ATSAM3A4CA-AU 概述
A microcontroller (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 computing hierarchy: microcontroller unit, embedded processor, system-on-chip. The SAM3A family sits within Microchip's (formerly Atmel) SMART ARM-based MCU portfolio, targeting industrial and connectivity applications where a balance of performance, integration, and cost is required.
Key features include the ARM Cortex-M3 revision 2.0 core with a Thumb-2 instruction set, a Memory Protection Unit (MPU), a 24-bit SysTick counter, and a Nested Vector Interrupt Controller (NVIC). On-chip analog integration comprises a 16-channel 12-bit ADC and two 12-bit DACs, while connectivity peripherals include CAN, I2C, IrDA, LIN, MMC/SDIO, SPI, SSC, UART/USART, and USB.
The dual-bank flash architecture supports in-application programming and firmware update strategies, allowing one bank to execute code while the other is reprogrammed. The wide 1.62V to 3.6V supply range and internal oscillator option simplify power-supply and clock design, and the operating range of -40C to +85C suits industrial environments.
Typical applications include industrial control and automation nodes, CAN-bus automotive and factory communication gateways, motor control systems, and embedded connectivity bridges using UART, SPI, and I2C peripherals.
Designers should budget flash and SRAM conservatively: 256 KB of flash and 64 KB of SRAM are ample for CAN protocol stacks and control loops, but larger RTOS-based designs may prefer the SAM3A8C with 512 KB of flash. Decouple all VDD/VDDIO pins and use the internal MPU to enforce task isolation in safety-minded firmware.
This page synthesizes distributor pricing, verified drop-in alternatives, and practical design notes not found in the manufacturer datasheet, based on data as of 2026-09-19.
直接替换替代料： ATSAM3A4CA-AU ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： ATSAM3A4CA-AU （相同外形与封装尺寸） ——差异在于 Connectivity, Flash Memory, SRAM, RoHS Status, Series.
快速对比工具——选择替代料号进行并排对比：
ATSAM3A8CA-AU
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$6.3 / 个
查看数据手册 →ATSAM3X4CA-AU
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
ATSAM3X8CA-AU
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$7.18 / 个
查看数据手册 →ATSAM3S4CA-AU
✅ 直接替换📋 参考替代料（不在目录中）
ATSAM3N4CA-AU
✅ 直接替换📋 参考替代料（不在目录中）
ATSAM4S16CA-AU
✅ 直接替换✓ 有现货
$5.55 / 个
查看数据手册 →ATSAM3A4CA-AU 最大额定值与电气特性
| Core Processor | ARM Cortex-M3 revision 2.0 |
| Core Size | 32-bit |
| Maximum Clock Speed | 84 MHz |
| Program Memory Size | 256 KB (2 x 128 KB banks) |
| Program Memory Type | FLASH |
| RAM Size | 64 KB (2 x 32 KB banks) |
| 电源电压 | 1.62 V to 3.6 V |
| Data Converters | A/D 16x12-bit; D/A 2x12-bit |
| Connectivity | CAN, I2C, IrDA, LIN, MMC, SPI, SSC, UART/USART, USB |
| Oscillator Type | Internal |
| Memory Protection | MPU (Memory Protection Unit) |
| Instruction Set | Thumb-2 |
| SysTick Counter | 24-bit |
| 工作温度 | -40C to +85C |
| 封装 | 100-LQFP (14 x 14 mm) |
| 安装类型 | Surface Mount |
| Series | SAM3A |
ATSAM3A4CA-AU 100-lqfp (14 x 14 mm) 引脚配置指南
ATSAM3A4CA-AU（100-lqfp (14 x 14 mm) 封装）的引脚配置。 该数字 IC 包含 GPIO、通信接口（UART、SPI、I2C）和电源引脚。请参阅制造商数据手册以了解复用引脚功能和配置选项。对嵌入式系统设计和 PCB 布局至关重要。
暂无详细引脚数据： ATSAM3A4CA-AU.
请参阅 数据手册 以查看完整引脚配置。
典型应用
ATSAM3A4CA-AU 适用于 6 应用s: Industrial Control and Automation Nodes, CAN Bus Communication Gateways, Motor Control Systems, USB and Serial Connectivity Bridges, Data Acquisition and Sensing Systems, Embedded IoT and Telemetry Devices.
Industrial Control and Automation Nodes
The ATSAM3A4CA-AU fits industrial control nodes where deterministic 84 MHz Cortex-M3 execution, a Memory Protection Unit, and rich serial connectivity meet the demands of PLC I/O modules, sensor hubs, and machine controllers. Its 16-channel 12-bit ADC acquires multiple analog sensor inputs under DMA without CPU intervention, while 256 KB of dual-bank flash accommodates control firmware plus a field-update bootloader. The -40C to +85C operating range covers cabinet-mounted industrial environments. Used as the main controller with UART and SPI-linked expansion modules, it delivers single-chip integration that reduces BOM count versus discrete MCU-plus-peripheral-logic designs; the MPU helps isolate safety-critical tasks from user firmware.
推荐
CAN Bus Communication Gateways
The on-chip CAN controller of the ATSAM3A4CA-AU makes it a natural fit for gateway and bridge nodes in automotive-adjacent and factory CAN networks. Paired with an external CAN transceiver, the MCU handles protocol framing, filtering, and mailbox management in hardware, offloading the Cortex-M3 core for routing and translation between CAN and USB, UART, or SPI links. The 64 KB banked SRAM buffers message queues during burst traffic, and the dual-bank flash enables remote firmware updates over the bus without bricking the node. Typical designs bridge a vehicle or machine CAN segment to a diagnostics or telemetry uplink, using the SSC peripheral for auxiliary audio or synchronous serial data capture.
推荐
Motor Control Systems
For brushed-DC and light servo motor control, the ATSAM3A4CA-AU combines its 12-bit ADC channels for current and position feedback with PWM outputs and fast interrupt latency from the Cortex-M3 NVIC. The 84 MHz core closes current loops in the tens-of-microseconds range typical of low- and medium-power drives, while hardware PWM peripherals generate the drive signals with minimal CPU overhead. The dual 12-bit DACs provide analog setpoints or reference generation, and the wide 1.62 V to 3.6 V supply simplifies interfacing with gate-driver logic. Designs requiring advanced sensorless FOC with high-resolution PWM should step up to the Cortex-M4-based ATSAM4S16CA-AU, which adds DSP instructions and an FPU.
推荐
USB and Serial Connectivity Bridges
With USB, multiple USARTs, SPI, I2C, and SSC on one chip, the ATSAM3A4CA-AU serves as a protocol bridge converting USB or UART traffic to SPI/I2C peripherals in industrial adapters, programming fixtures, and test equipment front-ends. The 256 KB flash holds USB stack, bridge firmware, and configuration tables simultaneously, and the banked SRAM sustains DMA-driven double-buffered endpoints without CPU stalls. Typical deployments include USB-to-CAN and USB-to-SPI adapters, where the internal oscillator reduces external component count. Performance consideration: the SAM3A USB peripheral runs at full speed (12 Mbps); applications needing 480 Mbps high-speed USB should select a SAM3X-series pin-compatible variant instead.
推荐
Data Acquisition and Sensing Systems
The 16-channel 12-bit ADC of the ATSAM3A4CA-AU enables multi-channel data acquisition front-ends for process monitoring, environmental sensing, and test instrumentation. Channels are scanned under hardware sequencer control with DMA transfers into either 32 KB SRAM bank, freeing the Cortex-M3 core for filtering, scaling, and communication tasks. The two 12-bit DAC outputs can drive analog control signals or serve as stimulus sources in stimulus-response test setups. With -40C to +85C operation and a wide supply range, nodes run directly from industrial 3.3 V rails. Designers should filter the analog reference and separate analog ground returns to preserve effective ADC resolution; effective-noise figures depend strongly on layout quality.
推荐
Embedded IoT and Telemetry Devices
The ATSAM3A4CA-AU powers IoT edge nodes and telemetry devices that aggregate sensor data and communicate over wired links such as RS-485, CAN, or Ethernet-adjacent bridges. Its 1.62 V to 3.6 V supply range and internal oscillator allow compact, battery-backed designs, while 256 KB flash accommodates application firmware plus an update agent using the dual-bank architecture for fail-safe over-the-air or field firmware upgrades. The MPU supports task isolation between the telemetry stack and safety routines. Combined with an external wireless module over UART or SPI, the MCU forms the local processing core; its USB device port doubles as a commissioning and diagnostics interface in the field.
推荐
推荐产品汇总
工程参考数据： ATSAM3A4CA-AU ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | ATSAM3A8CA-AU | ATSAM3X4CA-AU | ATSAM3S4CA-AU | ATSAM4S16CA-AU |
|---|---|---|---|---|---|
| Package | 100-LQFP (14 x 14 mm) | 100-LQFP (14 x 14 mm) - same | 100-LQFP (14 x 14 mm) - same | 100-LQFP (14 x 14 mm) - same | 100-LQFP (14 x 14 mm) - same |
| Brand | Microchip Technology (Atmel legacy) | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | ARM Cortex-M3 @ 84 MHz | ARM Cortex-M3 @ 84 MHz | ARM Cortex-M3 @ 84 MHz | ARM Cortex-M3 @ 84 MHz | ARM Cortex-M4 with FPU @ 120 MHz |
| Flash Memory | 256 KB (2 x 128 KB banks) | 512 KB (2 x 256 KB banks) | 256 KB (2 x 128 KB banks) | 256 KB | 1 MB |
| SRAM | 64 KB (2 x 32 KB banks) | 96 KB | 64 KB (2 x 32 KB banks) | 64 KB | 128 KB |
| CAN Controller | Yes | Yes | Yes | No | Yes |
| USB Speed | Full speed (device) | Full speed (device) | High speed (480 Mbps capable) | Full speed (device) | Full speed (device) |
关键差异点
- CAN connectivity retained at same cost tier （对比 ATSAM3S4CA-AU)
- Identical footprint with flash headroom path （对比 ATSAM3A8CA-AU)
- High-speed USB upgrade path in the same package （对比 ATSAM3X4CA-AU)
设计说明
Supply the ATSAM3A4CA-AU from a regulated 3.3 V rail within the 1.62 V to 3.6 V range. Place a 0.1 uF ceramic capacitor at every VDD/VDDIO pin pair plus one bulk 10 uF capacitor per supply domain, as close to the pins as possible. The internal regulator powers the Cortex-M3 core, so do not drive VDDCORE externally; follow the SAM3X/A datasheet power connection table. If brown-out behavior matters, enable and configure the on-chip brown-out detector rather than relying on external reset supervision alone.
The 100-pin LQFP (0.5 mm pitch) requires careful fanout: keep analog ADC input traces short and away from switching or high-drive outputs, and provide a solid ground plane under the package. Route the USB D+/D- pair as a matched-length 90-ohm differential pair if the device port is used. Assign the ADC reference its own filtered supply or a precision reference IC. Estimated: at 84 MHz with mostly-static CMOS loading, core current draw stays in the tens-of-mA range, so trace and via sizing follow standard 0.25 mm design rules comfortably.
Do not exceed 256 KB of flash budget in the linker map - the two 128 KB banks require the firmware linker script to place code and interrupts appropriately; spanning bank boundaries without a proper scatter/loader setup can cause hard faults. When using the dual-bank read-while-write feature for firmware updates, erase granularity and bank swap sequencing must follow the SAM3X/A flash controller (EEFC) commands exactly. Finally, the -AU LQFP has no exposed pad: thermal performance depends on copper pours connected to the ground pins.
合规信息
Abacus Technologies lists related SAM3A parts as EU RoHS and REACH compliant, but explicit compliance for the ATSAM3A4CA-AU ordering code was not stated in the retrieved data; verify on the Microchip product page. Not an automotive-qualified (-Q1 style) ordering code.