MCF51MM256VMB - 32-bit ColdFire V1 MCU, 256KB Flash 50MHz | NXP
MPN： MCF51MM256VMB ✗ 停產MCF51MM256VMB 概覽
A microcontroller unit (MCU) is a single-chip embedded computer that integrates a processor core, program memory, data memory, and peripheral functions on one die. Within the embedded systems hierarchy, the MCU sits below microprocessors in raw compute power but above discrete logic in integration, making it the workhorse of cost-sensitive, low-power control applications. The ColdFire V1 core from Freescale (now NXP) is a 32-bit architecture derived from the 68000 family, offering a favorable code-density and price point for handheld and metering products.
Key features of the MCF51MM256VMB include 256KB of on-chip flash program memory organized as 256K x 8, 32KB of RAM, and a rich connectivity set covering CANbus, external bus interface (EBI/EMI), I2C, SCI (UART), SPI, and USB On-The-Go. Peripheral functions include pulse-width modulation (PWM), a low-voltage detector (LVD), and a watchdog timer (WDT). The external oscillator type allows designers to choose precision clock sources for metering accuracy.
Architecturally, the device belongs to the low-cost, low-power, high-performance ColdFire V1 family explicitly designed for handheld metering devices, where battery life, integrated USB OTG for firmware updates, and CAN interfaces for utility networks are decisive. The 50MHz core speed provides sufficient headroom for metrology DSP-style computations while retaining single-supply low-power operation.
Typical applications include smart electricity, water, and gas meters, handheld data-collection terminals, industrial instrumentation front ends, and battery-powered equipment requiring USB connectivity for field servicing.
When designing with this part, note the lifecycle status: NXP lists the MCF51MM series as obsolete, so new designs should evaluate the available stock through authorized distributors or last-time-buy channels, and legacy designs should secure inventory or qualify a successor.
This page synthesizes distributor pricing, same-family drop-in alternatives, and sourcing-risk guidance not found in the manufacturer datasheet, giving engineers a single decision-ready reference as of 2026-10-18.
直接替換替代品，適用於 MCF51MM256VMB — 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： MCF51MM256VMB （相同外形與佔位） — 差異在於 Connectivity, Package, Product Type, CPU Core, Communication Interfaces.
MCF51MM128VMB
✅ 直接替換聯絡詢價
查看資料表 →MCF51JE256VMB
✅ 直接替換聯絡詢價
查看資料表 →MCF51MM256VMB 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 | 32K x 8 |
| Connectivity | CANbus, EBI/EMI, I2C, SCI, SPI, USB OTG |
| Peripherals | LVD, PWM, WDT |
| Number of I/O | 48 |
| Oscillator Type | External |
| 封裝 / 外殼 | 81-MAPBGA (10x10 mm) |
| 安裝類型 | Surface Mount |
| Packaging | Tray |
| Series | MCF51MM |
| Part Status | Obsolete |
| Supplier Device Package | 81-BGA |
MCF51MM256VMB 81-bga 腳位配置指南
MCF51MM256VMB（81-bga 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： MCF51MM256VMB.
請參閱 資料表 以查看完整腳位配置。
典型應用
MCF51MM256VMB 適用於 6 應用s: Handheld Metering Terminals, Smart Electricity Meters, Industrial Instrumentation, Battery-Powered Data Collectors, Building Automation Nodes, Medical Portable Diagnostic Devices.
Handheld Metering Terminals
The MCF51MM256VMB was purpose-built by Freescale/NXP for handheld metering devices. Its 50MHz ColdFire V1 core executes metrology algorithms with margin, while 256KB flash stores firmware plus tariff and billing tables and 32KB RAM buffers measurement sessions. USB On-The-Go enables direct field connection to laptops for data retrieval and firmware updates without extra bridge circuitry, and the external oscillator supports precision timing for energy-accuracy requirements. In this role the MCU integrates the entire control path - measurement sequencing via SPI-connected front ends, CAN or SCI communication to utility infrastructure, and low-power standby between readings, extending battery service intervals in field instruments.
推薦
Smart Electricity Meters
For residential and commercial electricity meters, the MCF51MM256VMB combines the three interfaces metering platforms need: CANbus for utility network communication, SCI UARTs for maintenance ports, and SPI/I2C for metering front-end ICs. The 256KB flash accommodates multi-tariff firmware, load-profile logging, and secure OTA-style update staging through USB OTG during factory or field programming. Its external oscillator input lets designers meet grid-timing accuracy class requirements with a temperature-compensated clock source. The low-voltage detector and watchdog timer provide the fail-safe behavior utilities expect, resetting the meter deterministically on brownout or firmware lockup events rather than allowing erroneous billing data.
推薦
Industrial Instrumentation
In portable and panel industrial instruments, the MCF51MM256VMB provides a 32-bit compute headroom advantage over 8-bit legacy MCUs at comparable cost. The external bus interface (EBI/EMI) allows direct attachment of parallel-bus display drivers or memory-mapped peripherals, while the 48 I/O lines handle keypad matrices, indicator outputs, and status inputs without expansion logic. CANbus integration connects the instrument to factory networks for condition monitoring, and SPI links to precision ADCs such as the CS5531 handle transducer signals. At 50MHz the core performs linearization, filtering, and calibration math in fixed point comfortably, and the 32KB RAM supports data logging between communication sessions in battery-backed designs.
推薦
Battery-Powered Data Collectors
Handheld data-collection terminals benefit from the MCF51MM family balance of performance and low power. The 50MHz ColdFire V1 core completes burst processing tasks quickly, allowing the MCU to return to low-power standby modes for most of the operating cycle - a pattern that dominates battery life in handheld use. USB OTG removes dock hardware: field operators sync readings directly to a PC or tablet through a standard cable. The 256KB flash retains collected records across battery swaps, and SCI/I2C links serve barcode or RFID front-end modules. The low-voltage detector warns of impending shutdown so the terminal can commit data structures safely before power loss.
推薦
Building Automation Nodes
The MCF51MM256VMB suits building-automation control nodes where CAN or SCI backbones connect sensors, actuators, and supervisory controllers. Its 48 I/O drive relays, valves, and damper signals directly through external drivers, while SPI-connected ADCs digitize temperature, humidity, and pressure sensor inputs. The 256KB flash stores protocol stacks and local control logic, and I2C handles configuration EEPROMs and real-time clocks. The watchdog timer guarantees that a stalled node recovers without technician intervention - essential in HVAC and access-control installations. Battery- or PoE-backed nodes also benefit from the LVD, which sequences a safe shutdown as supply voltage decays during outages.
推薦
Medical Portable Diagnostic Devices
Portable diagnostic instruments such as glucose meters and handheld vital-sign monitors fit the MCF51MM256VMB profile: low power for long battery sessions, a 32-bit core for signal processing, and USB OTG for uploading patient records to clinic systems. SPI-connected precision ADCs such as the PCM4202 or CS5531 acquire biosensor signals whose processing benefits from the 50MHz core's headroom. The 32KB RAM buffers session data, and 256KB flash holds calibration tables and patient-history records between uploads. The external oscillator supports the precise sample timing that medical measurement accuracy demands, while the watchdog provides the deterministic fault recovery expected in point-of-care equipment.
推薦
推薦產品摘要
工程參考資料，適用於 MCF51MM256VMB — 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 | MCF51MM128VMB | MCF51JE256VMB |
|---|---|---|---|
| Package | 81-MAPBGA (10x10 mm) | 81-MAPBGA (10x10 mm) - same | 81-MAPBGA (10x10 mm) - same |
| Brand | NXP (Freescale) | NXP (Freescale) | NXP (Freescale) |
| Core | ColdFire V1, 32-bit | ColdFire V1, 32-bit | ColdFire V1, 32-bit |
| Max Clock Speed | 50 MHz | 50 MHz | 50 MHz |
| Program Flash | 256 KB | 128 KB | 256 KB |
| Lifecycle Status | Obsolete | Obsolete | Obsolete |
主要差異化特點
- Double the program flash for feature-rich meter firmware (對比MCF51MM128VMB)
- Metering-optimized peripheral set with USB OTG (對比MCF51JE256VMB)
- Obsolescence is the honest trade-off (對比Active NXP Cortex-M MCUs)
設計說明
The MCF51MM256VMB is obsolete: NXP no longer manufactures it, and remaining supply flows through aftermarket sources (Heisener reported 2,192 pieces as of 2026-10-18; Rochester Electronics carries legacy stock). Before committing a production build, confirm lot date codes and request certificate of conformity from the broker, since obsolete parts carry elevated counterfeit risk. For sustaining designs, initiate a last-time-buy sized to expected field-service demand, and in parallel evaluate migration to NXP Kinetis or LPC Cortex-M families for the next board revision.
The 81-MAPBGA (10x10 mm) package requires a 0.8 mm-pitch BGA land pattern with via-in-pad or dog-bone fanout on inner rows. Escape routing the 48 I/O plus power balls typically needs at least four layers. Follow the land pattern in the NXP MCF51MM256 datasheet mechanical drawing, and specify NSMD pads for reliable solder joints. BGA rework demands X-ray inspection capability - plan inspection coverage in your manufacturing flow, since solder bridges under the package are invisible optically.
The device uses an external oscillator, so clock integrity depends on PCB layout: keep the oscillator loop short, guard it with ground, and isolate it from switching noise of CAN transceivers and USB PHY circuitry. Decouple all VDD balls with 100 nF ceramics placed on the BGA fanout layer, plus bulk capacitance near the supply entry. The low-voltage detector (LVD) should be enabled in firmware so brownout events trigger a deterministic reset rather than flash corruption - important for meters that must never lose billing data.
合規資訊
Compliance data was not present in the provided web data. As an obsolete part, original RoHS declarations should be requested from NXP legacy product services or Rochester Electronics.