MCF51AC256BCLKE - 32-bit ColdFire V1 MCU, 256KB Flash, 50MHz | NXP
MPN： MCF51AC256BCLKE ✗ 停產MCF51AC256BCLKE 概覽
A microcontroller (MCU) is a single integrated circuit that combines a processor core, program memory, data memory, and peripherals such as timers, serial interfaces, and watchdogs into one chip. MCUs sit at the top of the embedded-system hierarchy and serve as the main control element in appliances, meters, motor controls, and industrial automation equipment.
Key features of the MCF51AC256BCLKE include 256KB (256K x 8) of on-chip Flash program memory, 32KB of RAM, connectivity through I2C, SCI (UART), and SPI interfaces, and peripherals including low-voltage detection (LVD), PWM modules, and a watchdog timer (WDT). With 69 general-purpose I/O lines, the device offers generous pin resources in the compact 14x14 mm LQFP-80 footprint.
Technically, the ColdFire V1 core is a 32-bit variable-length RISC processor that executes efficient code with low gate count, delivering 50MHz performance at very low cost and power. The Flexis Controller Continuum architecture means code and tools migrate smoothly between the S08AC 8-bit devices and the MCF51AC 32-bit devices, reducing redesign risk when application demands grow.
Typical applications include consumer appliance control, industrial automation and sensing nodes, low-cost motor control with PWM, metering systems, and human-interface boards that need many GPIO and standard serial links (I2C, SPI, UART/SCI).
When designing with this part, verify its End-of-Life status on the NXP product page and plan a migration path; the pin-compatible MCF51AC256ACLKE and other LQFP-80 family members are the natural successors within the same footprint.
This page synthesizes verified distributor pricing, drop-in family alternatives, application guidance, and design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 MCF51AC256BCLKE — 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。
此系列的變體
與下列產品可直接替換的同系列型號： MCF51AC256BCLKE （相同外形與佔位） — 差異在於 Package, Core Processor, Flash Memory, Mounting Type, ADC.
MCF51AC256ACLKE
✅ 直接替換📋 參考替代品（不在目錄中）
MCF51AC256BCLKER
✅ 直接替換📋 參考替代品（不在目錄中）
MCF51AC128BCLKE
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MCF51AC256BCLKE-QF
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MCF51AC256BCLKE 最大額定值與電氣特性
| Core Processor | ColdFire V1 |
| Core Size | 32-bit |
| Maximum Clock Speed | 50 MHz |
| Program Memory Size | 256 KB (256K x 8) |
| Program Memory Type | FLASH |
| RAM Size | 32 KB |
| EEPROM Size | N/A |
| Connectivity | I2C, SCI, SPI |
| Peripherals | LVD, PWM, WDT |
| Number of I/O | 69 |
| 封裝 | LQFP-80 (14x14 mm) |
| 安裝類型 | Surface Mount |
| Series | MCF51AC (Flexis) |
| Part Status | End of Life (per NXP product page) |
MCF51AC256BCLKE lqfp-80 (14x14 mm) 腳位配置指南
MCF51AC256BCLKE（lqfp-80 (14x14 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： MCF51AC256BCLKE.
請參閱 資料表 以查看完整腳位配置。
典型應用
MCF51AC256BCLKE 適用於 6 應用s: Appliance Control Boards, Industrial Automation and Sensing Nodes, Low-Cost Motor Control, Metering and Data Loggers, Human Interface and Display Controllers, Legacy System Maintenance and BOM Continuity.
Appliance Control Boards
The MCF51AC256BCLKE fits appliance control such as washers, cookers, and HVAC controllers because its 256KB Flash holds feature-rich firmware including UI logic and communication stacks, while the 50MHz ColdFire V1 core executes control loops deterministically. The 69 GPIO drive relays, buttons, LEDs, and displays directly, and I2C/SPI connect sensors and EEPROMs. PWM outputs handle heater or fan control. Because Flexis parts are tool-compatible with S08AC 8-bit devices, appliance makers can scale designs up or down without changing toolchains. Note the EOL status: design updates should target the pin-compatible family successors.
推薦
Industrial Automation and Sensing Nodes
In factory automation nodes, the MCF51AC256BCLKE combines a 32-bit 50MHz ColdFire V1 core with I2C, SPI, and SCI (UART) links suited to MODBUS-style serial communication and sensor acquisition. The 32KB RAM buffers sensor data and protocol frames, while the watchdog timer (WDT) and low-voltage detection (LVD) improve field robustness - both are mandatory features in industrial environments where brownouts and hangs must be handled autonomously. With 256KB Flash, protocol stacks plus diagnostics coexist comfortably. Choose the pin-compatible MCF51AC256ACLKE for new sourcing given the EOL designation of the 'B' part.
推薦
Low-Cost Motor Control
The integrated PWM peripherals of the MCF51AC256BCLKE make it a fit for fan, pump, and small motor control. The 50MHz 32-bit core runs PID or commutation firmware with margin, PWM outputs drive power stages through gate drivers, and the LVD protects against unsafe operation during supply dips. 69 GPIO allow interfacing with hall sensors, encoders, and fault-feedback lines simultaneously. Since 256KB Flash exceeds typical motor-control needs, firmware growth (diagnostics, fieldbus) is absorbed without a redesign - a common constraint on smaller MCUs. Respect the EOL status in new designs and validate the MCF51AC256ACLKE as successor.
推薦
Metering and Data Loggers
Utility metering and data-logging products benefit from the MCF51AC256BCLKE's 256KB Flash (firmware plus calibration tables plus logging headroom) and 32KB RAM for record buffers. SCI/UART handles meter-bus style communication, I2C connects RTCs and EEPROMs, and SPI interfaces precision ADC front ends for measurement channels. The 50MHz ColdFire V1 core performs accumulation and scaling math faster than typical 8-bit parts at a similar cost point, thanks to the Flexis positioning at the low end of the 32-bit ColdFire family. Power and temperature limits should be confirmed in the NXP datasheet for the meter environment.
推薦
Human Interface and Display Controllers
With 69 GPIO, the MCF51AC256BCLKE can directly drive segmented LCD alternatives such as LED matrices, keypads, and indicator arrays, while SCI/I2C links talk to host processors. The 256KB Flash accommodates graphics tables and multi-language strings, and the 50MHz core keeps scan and debounce loops responsive. PWM channels support backlight dimming and buzzer tones. The Flexis tool compatibility allows a single engineering team to maintain both 8-bit (S08AC) low-cost HMI variants and this 32-bit variant with shared code. For new layouts, source the pin-compatible MCF51AC256ACLKE instead of the EOL 'B' version.
推薦
Legacy System Maintenance and BOM Continuity
A major remaining use of the MCF51AC256BCLKE is sustaining production of existing designs after NXP declared End of Life. Because the Flexis MCF51AC256 family is pin-, peripheral-, and tool-compatible, boards can be re-populated with the MCF51AC256ACLKE (same LQFP-80 footprint, same 256KB/32KB memory) with minimal revalidation. The tape-and-reel MCF51AC256BCLKER remains available at DigiKey, extending buy time. Engineers should secure last-time-buy stock now and prepare firmware regression tests against the 'A' variant to de-risk the transition, documenting any errata differences between revisions.
推薦
推薦產品摘要
工程參考資料，適用於 MCF51AC256BCLKE — 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 | MCF51AC256ACLKE | MCF51AC256BCLKER | MCF51AC128BCLKE | MCF51AC256BCLKE-QF |
|---|---|---|---|---|---|
| Package | LQFP-80 (14x14 mm) | LQFP-80 (14x14 mm) - same | LQFP-80 (14x14 mm) - same | LQFP-80 (14x14 mm) - same | LQFP-80 (14x14 mm) - same |
| Brand | NXP Semiconductors (Freescale legacy) | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Core / Speed | ColdFire V1, 32-bit, 50 MHz | ColdFire V1, 32-bit, 50 MHz | ColdFire V1, 32-bit, 50 MHz | ColdFire V1, 32-bit, 50 MHz | ColdFire V1, 32-bit, 50 MHz |
| Flash | 256 KB | 256 KB | 256 KB | 128 KB | 256 KB |
| RAM | 32 KB | 32 KB | 32 KB | 16 KB | 32 KB |
| GPIO Count | 69 | 69 | 69 | 69 | 69 |
主要差異化特點
- Larger memory than 128KB family siblings (對比MCF51AC128BCLKE)
- Newer 'B' silicon revision (對比MCF51AC256ACLKE)
- Flexis tool compatibility (對比MC9S08AC family 8-bit devices)
設計說明
The MCF51AC256BCLKE is officially End of Life per the NXP product page. Before committing any new PCB spin, confirm remaining lifetime buys and validate the pin-compatible MCF51AC256ACLKE (same LQFP-80 footprint, same 256KB Flash) on your board. Keep at least one full production lot of the 'B' part as a reference lot for regression comparison, and record errata differences between the 'A' and 'B' silicon revisions in your design documentation.
The LQFP-80 (14x14 mm) footprint uses 0.5 mm pitch gull-wing leads; specify the land pattern per the NXP MCF51AC256 datasheet package drawing rather than generic IPC calculators. Decouple the VDD pins with 100 nF ceramics placed within 2 mm of each supply pin plus one bulk 4.7-10 uF per rail (estimated values - confirm against the datasheet power recommendations). The exposed no-connect corners of the LQFP should remain free of traces to aid inspection of all 80 joints.
Use the on-chip low-voltage detection (LVD) and watchdog timer (WDT) in every build - they are free features on this MCU and protect field units from brownout-induced corruption. Estimated: at 50MHz the ColdFire V1 core current is in the tens of mA range (exact figure available in the NXP datasheet), so a single 3.3V LDO rated at 100-150 mA covers the MCU plus typical I2C/SPI peripherals with margin. Sequence power so GPIO do not back-drive unpowered peripherals through the 69 I/O lines.
合規資訊
The NXP product page includes an Environmental Quality tab, but compliance specifics for this MPN were not present in the verified web data and are marked unknown.
