NUC120RD3AN - 32-bit Cortex-M0 MCU 64KB Flash 64-LQFP | Nuvoton
MPN： NUC120RD3AN ✗ 停產NUC120RD3AN 概覽
A microcontroller (MCU) is a single integrated circuit that combines a processor core, memory, and peripherals into one chip, forming the lowest tier of the embedded processing hierarchy: MCU -> embedded processor -> SoC. The ARM Cortex-M0 core used here is the most energy-efficient 32-bit ARM processor, delivering performance comparable to many 16-bit MCUs at a cost equivalent to traditional 8-bit devices, which is why it is widely used as an 8-bit replacement in cost-sensitive designs.
Key features of the NUC120RD3AN include USB 2.0 device connectivity, a rich peripheral set (I2C, SPI, UART/USART, IrDA, I2S, PWM, EBI/EMI), and support functions such as brown-out detect/reset, DMA, low-voltage detect, power-on reset, and a watchdog timer. The internal oscillator eliminates the need for an external crystal in many designs, and four-level priority NVIC interrupt handling supports 32 interrupt inputs.
Architecturally, the device couples the Cortex-M0 core with the NuMicro NUC100-series peripheral fabric; Keil MDK device support confirms full CMSIS-compliant toolchain compatibility for the NUC120RD3AN.
Typical applications include USB-connected industrial controllers, consumer appliance control panels, motor control with PWM, and communication bridges using its multiple serial interfaces.
Design consideration: confirm supply window (3.3V/5V tolerant operation) and verify Flash/RAM sizing against application footprint, as 64KB/16KB is adequate for most control tasks but not for large protocol stacks.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 NUC120RD3AN — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
NUC120RD2BN
✅ 直接替換📋 參考替代品（不在目錄中）
NUC123LD4AN0
✅ 直接替換📋 參考替代品（不在目錄中）
NUC120RE3AN
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
NUC120LE3AN
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
NUC120LD3AN
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
NUC120RD3AN 最大額定值與電氣特性
| Core Processor | ARM Cortex-M0 |
| Core Size | 32-bit |
| Maximum Clock Speed | 50 MHz |
| Program Memory Size | 64KB (64K x 8) |
| Program Memory Type | FLASH |
| RAM Size | 16K x 8 |
| Number of I/O | 45 |
| 供應電壓 | 3.3V / 5V |
| Connectivity | EBI/EMI, I2C, IrDA, SPI, UART/USART, USB |
| Peripherals | Brown-out Detect/Reset, DMA, I2S, LVD, POR, PS2, PWM, WDT |
| Oscillator Type | Internal |
| Interrupt Inputs | 32 (NVIC, 4-level priority) |
| 封裝 / 外殼 | 64-LQFP (7x7 mm) |
| 安裝類型 | Surface Mount |
| Series | NuMicro NUC120 |
| Part Status | Obsolete |
NUC120RD3AN 64-lqfp (7x7 mm) 腳位配置指南
NUC120RD3AN（64-lqfp (7x7 mm) 封裝）的腳位配置。 此數位 IC 包含 GPIO、通訊介面（UART、SPI、I2C）與電源腳位。替代腳位功能與配置選項請參閱製造商資料表。對嵌入式系統設計與 PCB 佈局至關重要。
無詳細腳位定義資料： NUC120RD3AN.
請參閱 資料表 以查看完整腳位配置。
典型應用
NUC120RD3AN 適用於 6 應用s: USB Industrial Controllers, Appliance and Consumer Control Panels, Motor Control with PWM, Communication Bridges and Protocol Converters, Audio Peripherals and I2S Devices, Legacy Board Repair and Last-Time-Buy Replacement.
USB Industrial Controllers
The NUC120RD3AN fits USB-connected industrial control nodes because it combines USB 2.0 device connectivity with industrial-grade peripherals such as PWM, DMA, EBI/EMI external bus, and watchdog/brown-out supervision. Its 50 MHz Cortex-M0 core handles USB HID/CDC class communication while simultaneously running the control loop, and the 45 GPIO lines drive relays, optocouplers, and status indicators directly. The 3.3V/5V supply window simplifies integration into legacy 5V industrial panels. Placed as the main controller with external MOSFET drivers on PWM outputs, it delivers deterministic interrupt response via the 4-level NVIC. Trade-off: 64KB Flash accommodates typical USB stacks but leaves limited headroom for additional protocol layers.
推薦
Appliance and Consumer Control Panels
Cost-sensitive appliance control panels benefit from the NUC120RD3AN's combination of 8-bit-MCU-equivalent cost and 32-bit performance. The internal oscillator removes the external crystal BOM line in non-USB or tolerant-timing designs, while brown-out detect/reset, power-on reset, and watchdog timer provide the supervision required for mains-powered consumer products. The 45 GPIO with PWM outputs drive LED segments, keypads, and small motor or heater controls, and the I2C/SPI interfaces connect display drivers and EEPROMs. Its 3.3V/5V operation suits transformer or linear supplies common in appliances. The 64-pin LQFP (7x7 mm) surface-mount package keeps two-layer PCB layouts compact at volume-oriented cost points.
推薦
Motor Control with PWM
The NUC120RD3AN suits small motor control applications - fans, pumps, and light actuator drives - thanks to its PWM peripherals, DMA support, and 50 MHz real-time interrupt capability. The Cortex-M0 core executes commutation or speed-loop code deterministically, while hardware PWM channels generate drive waveforms without CPU loading. GPIO counts allow rotor-position sensor inputs plus fault monitoring lines, and the I2C interface can read external current/voltage monitors. Integrated brown-out and watchdog protection enhances system safety during supply dips typical of motor start-up. Designers should budget code space carefully: 64KB Flash fits sensorless control algorithms but large field-oriented-control libraries may need the larger-memory NUC123 variants.
推薦
Communication Bridges and Protocol Converters
With UART/USART, SPI, I2C, IrDA, and USB interfaces all on-chip, the NUC120RD3AN is well positioned as a protocol converter between legacy serial equipment and USB hosts. The 16KB SRAM provides buffering for packet reassembly and framing, and DMA offloads byte-level transfers to sustain throughput at 50 MHz. Typical deployments include USB-to-RS485 converters, IrDA bridges for metering, and industrial gateway front ends when combined with external transceivers. The EBI/EMI interface additionally permits memory-mapped attachment of external peripherals. The principal limitation is Flash capacity: 64KB accommodates two-to-three protocol stacks, so designs aggregating many protocols should evaluate the NUC123LD4AN0 successor.
推薦
Audio Peripherals and I2S Devices
The NUC120RD3AN includes an I2S peripheral, enabling USB audio-class accessories, voice-command front ends, and simple digital-audio bridging. As a USB device controller paired with I2S output, it can stream audio from a PC to external DACs for headsets and speaker systems, while the 50 MHz core handles USB endpoint servicing and descriptor management. The 45 GPIO lines support buttons, volume encoders, and LED indication, and SPI connects volume/EQ controllers. The main constraint is that USB audio applications consume a significant share of the 64KB Flash; firmware must be lean. The 3.3V I/O domain interfaces cleanly with standard audio codecs and DACs without level shifting.
推薦
Legacy Board Repair and Last-Time-Buy Replacement
Because the NUC120RD3AN is obsolete, its remaining practical application is sustaining production and repair of existing NuMicro NUC120-based boards. XAIPART and secondary distributors (Jotrin, Xecor, Veswin, Avaq) still supply verified-stock parts for these scenarios. When sourcing, buyers should validate date codes and authenticity, since obsolete MCUs are frequent counterfeit targets, and should simultaneously qualify the NUC123LD4AN0 or NUC120RD2BN as continuation paths. For PCAs where the LQFP-64 footprint must be preserved, same-family Nuvoton parts minimize requalification to a pinout and supply-range check. This application profile - not new design starts - is now the dominant use case for this MPN as of 2026.
推薦
推薦產品摘要
工程參考資料，適用於 NUC120RD3AN — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | NUC120RD2BN | NUC123LD4AN0 | NUC120LE3AN |
|---|---|---|---|---|
| Package | 64-LQFP (7x7 mm) | 64-LQFP (7x7 mm) - same | 64-LQFP - same family | 64-LQFP (7x7 mm) - same |
| Brand | Nuvoton Technology | Nuvoton Technology | Nuvoton Technology | Nuvoton Technology |
| Core / Speed | ARM Cortex-M0, 50 MHz | ARM Cortex-M0, 50 MHz | ARM Cortex-M0, faster generation | ARM Cortex-M0, 50 MHz |
| Supply Voltage | 3.3V / 5V | 3.3V / 5V | 2.5V-5.5V class (verify datasheet) | 3.3V / 5V |
主要差異化特點
- USB 2.0 device connectivity at 8-bit-MCU-class cost (對比NUC120LE3AN)
- Active-generation successor available (對比NUC123LD4AN0)
- Integrated supervision reduces external BOM (對比NUC120RD2BN)
設計說明
The NUC120RD3AN carries obsolete status, so it must not be selected for new designs. If used for legacy sustenance, verify supply authenticity (date codes, distributor traceability) since obsolete MCUs are common counterfeit targets. When qualifying a successor, verify pin-to-pin compatibility against the official Nuvoton datasheet ordering table - suffix codes encode Flash/RAM/package combinations that are easy to misread.
The device operates from a 3.3V/5V supply window. Decouple VDD with 0.1uF ceramic capacitors at each power pin plus bulk 10uF, and tie VSS pins solidly to the ground plane. The internal oscillator reduces BOM cost, but for USB compliance and timing-critical UART/I2S work, use the appropriate external crystal configuration per the Nuvoton NUC120 datasheet clock section. Brown-out detect settings should be enabled for 5V systems to ride through supply dips safely.
For the 64-LQFP (7x7 mm) footprint, place the decoupling capacitors within 2-3 mm of the supply pins and route USB D+/D- as a 90-ohm differential pair with length matching when the USB device interface is used. Assign PWM and I2S signals away from the crystal traces to minimize coupled jitter. Keil MDK and Nuvoton NuLink tooling assume standard SWD pin access - keep the SWD header pads on the PCB for firmware updates and factory programming.
合規資訊
Compliance status not stated in the provided web data; verify on the official Nuvoton product page or datasheet before procurement.
