NXP Semiconductors MCF51AC256BCLKER

Overview

MCF51AC256BCLKER from NXP Semiconductors (formerly Freescale) is a 32-bit ColdFire V1 microcontroller without CAN interface, operating up to 50.33 MHz with 256 KB flash and 32 KB SRAM, featuring 24-channel 12-bit ADC, dual analog comparators, and dual FTM modules - used in industrial motor control and embedded HMI systems.

For engineers reviewing the MCF51AC256BCLKER datasheet, MCF51AC256BCLKER pinout, MCF51AC256BCLKER application, or MCF51AC256BCLKER equivalent, key selection criteria include its 80-pin LQFP package, –40°C to 85°C temperature grade, absence of CAN peripheral, and support for rapid GPIO, SPI2 with FIFO, and hardware CRC acceleration.

Technical Context

The MCF51AC256BCLKER implements the ColdFire V1 core with ISA_C instruction set, delivering 0.76 DMIPS/MHz when executing from flash and supporting background debug via single-wire BDM. Its multipurpose clock generator (MCG) integrates FLL/PLL with trimmable internal reference (±2% deviation) and supports crystal (1–16 MHz) or ceramic resonator inputs.

System-level integration includes two flexible timer modules (FTM1 and FTM2), each with six channels supporting input capture, edge-aligned or center-aligned PWM, deadtime insertion, and ADC hardware triggering. The device lacks CAN but retains full MSCAN-compatible register mapping except for transmit/receive buffer logic - enabling software reuse in non-CAN variants.

Key Specifications

Pinout & Package

Package: 80-pin LQFP, 14 mm × 14 mm, 0.5 mm pitch, RoHS-compliant (E suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with Kinetis K22FN512VLH12, the MCF51AC256BCLKER provides ColdFire ISA continuity and lower power at moderate performance; compared with MCF51JM128CLKER, it doubles flash and RAM while adding a second FTM - critical for dual-motor or multi-axis control.

Availability

MCF51AC256BCLKER is available at Aetrix Electronics and suitable for industrial motor control, embedded HMI, PLC I/O modules, and smart sensor nodes requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MCF51AC256BCLKER 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.

The MCF51AC256 series belongs to NXP's ColdFire microcontroller family, designed specifically as a 32-bit upgrade path from 8-bit S08 devices - emphasizing mixed-signal integration, deterministic real-time control, and debug visibility for industrial edge applications.

FAQ

What is the maximum operating frequency of the MCF51AC256BCLKER?

The MCF51AC256BCLKER operates at a maximum core frequency of 50.33 MHz across its full voltage range (2.7–5.5 V) and temperature grade (–40°C to +85°C). This speed is achievable in PEE mode using the MCG's PLL with an external crystal input, and the device delivers 0.76 DMIPS per MHz when executing code from flash memory. The MCF51AC256BCLKER maintains timing compliance under worst-case conditions as specified in Section 2.11 of its datasheet.

Does the MCF51AC256BCLKER include a CAN controller?

No, the MCF51AC256BCLKER does not include a CAN controller. The 'B' in its part number explicitly denotes the CAN-disabled variant, confirmed in Table 1 of the datasheet and the device comparison section. Pins PTA0 (TxCAN) and PTA1 (RxCAN) are reserved as general-purpose I/O or no-connect in this version. All CAN-related registers and interrupt vectors remain unimplemented, distinguishing it from the 'A' variant (e.g., MCF51AC256AVLKE).

What package and pin count does the MCF51AC256BCLKER use?

The MCF51AC256BCLKER uses an 80-pin LQFP package measuring 14 mm × 14 mm with 0.5 mm pitch, designated by the 'LKE' suffix per Freescale's part numbering scheme. This matches the pinout shown in Figure 2 of the datasheet, supporting all 69 GPIOs, dual FTM modules, 24 ADC channels, and full peripheral routing - excluding CAN signals. The package is RoHS-compliant and rated for industrial temperature operation.

How much flash and RAM memory does the MCF51AC256BCLKER have?

The MCF51AC256BCLKER integrates 256 KB of on-chip flash memory and 32 KB of static RAM (SRAM). Both memory blocks support full read/program/erase operation across the device's rated voltage (2.7–5.5 V) and temperature (–40°C to +85°C) ranges. Flash includes block protection features, and SRAM supports security locking to prevent unauthorized access - details are specified in Sections 2.5 and 2.13 of the official datasheet.

What debug interface does the MCF51AC256BCLKER support?

The MCF51AC256BCLKER supports a single-wire background debug module (BDM) via the BKGD/MS pin, compatible with standard ColdFire debug tools. It provides real-time program trace through the debug visibility bus (VBUS), six hardware breakpoints (four PC, one address pair, one data), and on-chip trace buffer with configurable start/stop conditions. No JTAG interface is present - all debug functionality is implemented per the V1 ColdFire core specification in the MCF51AC256 datasheet.