NXP Semiconductors MCF5281CVF66

Overview

MCF5281CVF66 from NXP (formerly Freescale) is a 32-bit ColdFire V2 core microcontroller featuring a 66 MHz maximum CPU frequency, 256 KB on-chip Flash memory, 32 KB SRAM, and integrated peripherals including FlexCAN, QSPI, I²C, UARTs, QADC, and FEC Ethernet controller. It targets industrial control, networked automation, and embedded communications systems requiring deterministic real-time performance and mixed-signal connectivity.

For engineers reviewing the MCF5281CVF66 datasheet, MCF5281CVF66 pinout, MCF5281CVF66 application, or MCF5281CVF66 equivalent, key selection criteria include its 66 MHz ColdFire V2 core with EMAC unit, 256 KB flash/32 KB RAM memory map, 144-pin LQFP package, FlexCAN 2.0B compliance, and support for external SDRAM via EIM - all critical for deterministic control loop execution and multi-protocol fieldbus integration.

Technical Context

The MCF5281CVF66 implements the ColdFire V2 microarchitecture with a 5-stage pipeline, 4 KB instruction/data unified cache, and enhanced multiply-accumulate (EMAC) unit supporting fractional arithmetic. Its memory subsystem includes configurable chip select logic, an External Interface Module (EIM) for SDRAM and SRAM expansion, and a ColdFire Flash Module with security and protection registers.

Peripherals are managed through dedicated modules: FlexCAN handles CAN 2.0B frames with 64-message buffers; QSPI supports daisy-chain SPI devices with DMA; QADC provides 12-bit conversion across 16 channels with queue-based triggering; and the Fast Ethernet Controller (FEC) delivers IEEE 802.3-compliant 10/100 Mbps MAC functionality with internal PHY interface signals.

Key Specifications

Pinout & Package

Package: 144-pin LQFP (20 mm × 20 mm, 0.5 mm pitch), RoHS-compliant, surface-mount. Thermal pad on underside for enhanced heat dissipation in industrial ambient conditions.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microcontroller applications.

Compared with MCF5282CVF66, the MCF5281CVF66 omits one UART and the full MII PHY interface pins - reducing pin count and power consumption while retaining identical CAN, QSPI, and QADC capability. Against K60DN512ZVMD10, it trades ARM ecosystem advantages for deterministic ColdFire real-time behavior and proven industrial qualification.

Availability

MCF5281CVF66 is available at Aetrix Electronics and suitable for industrial PLC controllers, building automation gateways, networked motor drives, and energy metering nodes requiring stable component supply and long-term manufacturability.

Supply support for MCF5281CVF66 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with deep heritage in microcontroller innovation through its acquisition of Freescale Semiconductor.

The MCF5281CVF66 belongs to the ColdFire V2 microcontroller family, designed specifically for deterministic real-time control in harsh industrial environments - emphasizing low-latency interrupt response, on-chip mixed-signal integration, and long-lifecycle support.

FAQ

What is the maximum operating frequency of the MCF5281CVF66?

The MCF5281CVF66 operates at a maximum CPU frequency of 66 MHz, achieved via its integrated Phase-Locked Loop (PLL) with programmable multiplication factor. This frequency governs instruction execution speed, peripheral clock domains derived from the core clock, and timing margins for external bus interfaces such as QSPI and EIM. The device maintains stability across industrial temperature ranges (–40°C to +85°C) at this rating.

Does the MCF5281CVF66 include an integrated Ethernet PHY?

No, the MCF5281CVF66 integrates only the Fast Ethernet Controller (FEC) MAC layer. It requires an external 10/100 Mbps PHY IC (e.g., DP83848 or LAN8720) connected via MII or RMII signals. Unlike the MCF5282CVF66, it does not include the full MII pin set - confirming its role as a MAC-only solution dependent on external PHY hardware for physical layer signaling.

How much on-chip Flash and SRAM does the MCF5281CVF66 provide?

The MCF5281CVF66 integrates 256 KB of on-chip Flash memory and 32 KB of on-chip SRAM. The Flash is organized into blocks with configurable protection via the CFMPROT register and supports in-application programming. The SRAM is zero-wait-state at full CPU speed and is mapped into the ColdFire linear address space starting at 0x20000000, enabling fast data access for stacks, buffers, and real-time variables.

What CAN protocol versions does the FlexCAN module in the MCF5281CVF66 support?

The FlexCAN module in the MCF5281CVF66 supports CAN 2.0B protocol exclusively, including both standard (11-bit) and extended (29-bit) identifier frames. It implements full CAN message buffering (64 message objects), hardware acceptance filtering, and automatic retransmission - meeting ISO 11898-1 requirements for robust fieldbus communication in industrial automation and vehicle subsystems.

Is the MCF5281CVF66 pin-compatible with other ColdFire family members?

The MCF5281CVF66 is pin-compatible with the MCF5282CVF66 in the 144-pin LQFP package, sharing identical signal assignments for core functions, memory interfaces, and major peripherals. However, MCF5282CVF66 exposes additional MII signals and a third UART that are unconnected (NC) on the MCF5281CVF66 - making MCF5281CVF66 a functional subset suitable for designs not requiring those extra resources.