NXP Semiconductors MCF51AC256BVPUE

Overview

MCF51AC256BVPUE from NXP Semiconductors (formerly Freescale) is a 32-bit ColdFire V1 microcontroller without CAN interface, housed in a 64-pin LQFP package. It operates up to 50.33 MHz, integrates 256 KB flash and 32 KB SRAM, features a 12-bit ADC with 24 channels, dual analog comparators, and supports SPI, I²C, SCI, FTM, TPM, CRC, and KBI - deployed in industrial motor control and sensor-based embedded systems.

For engineers reviewing the MCF51AC256BVPUE datasheet, MCF51AC256BVPUE pinout, MCF51AC256BVPUE application, or MCF51AC256BVPUE equivalent, key selection criteria include its 64-pin LQFP footprint, absence of CAN peripheral, 256 KB/32 KB memory configuration, V1 ColdFire core performance at 50.33 MHz, and support for low-power stop/wait modes with rapid GPIO access.

Technical Context

The MCF51AC256BVPUE implements the ColdFire V1 core with ISA_C instruction set, delivering 0.76 DMIPS/MHz when executing from flash and 0.94 DMIPS/MHz from SRAM. Its multipurpose clock generator (MCG) supports FLL/PLL operation with crystal (1–16 MHz) or ceramic resonator inputs, and includes an independent low-power oscillator (LPO) for COP and RTI.

It integrates two flexible timer modules (FTM1 and FTM2), each supporting input capture, output compare, edge- or center-aligned PWM, deadtime insertion, and hardware-triggered ADC conversions. The device lacks CAN functionality (confirmed by part number suffix 'B' and Table 1), distinguishing it from 'A' variants, and uses a dedicated background debug module (BDM) with single-wire interface and real-time trace via VBUS.

Key Specifications

Pinout & Package

The MCF51AC256BVPUE is supplied in a 64-pin LQFP package (10 mm × 10 mm, 0.5 mm pitch), thermally enhanced with exposed pad per Freescale mechanical drawing. Pin assignments align with Figure 3 of Rev.7 datasheet, excluding TxCAN (PTA0) and RxCAN (PTA1) functions as confirmed by 'B' variant designation and Table 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCF51AC256AVPUE, the MCF51AC256BVPUE removes CAN hardware to reduce cost and complexity in point-to-point serial or SPI/I²C-based systems; versus Kinetis K22, it offers ColdFire toolchain continuity and lower power at reduced compute density, making it optimal for legacy migration or cost-sensitive industrial control.

Availability

MCF51AC256BVPUE is available at Aetrix Electronics and suitable for industrial motor control, smart sensor nodes, PLC I/O modules, and industrial HMI controllers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MCF51AC256BVPUE 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 acquired Freescale in 2015 and maintains the ColdFire portfolio for industrial and automotive microcontroller applications requiring deterministic real-time performance and long-term supply assurance.

The MCF51AC256 series belongs to NXP's legacy ColdFire microcontroller product line, designed specifically for cost-sensitive, high-reliability embedded control applications where 32-bit processing, integrated analog peripherals, and robust debug capabilities are essential.

FAQ

What is the maximum operating frequency of the MCF51AC256BVPUE?

The MCF51AC256BVPUE operates at a maximum core frequency of 50.33 MHz across its full voltage range (2.7 V to 5.5 V). This speed is achievable using the MCG's PLL mode with an external crystal reference, and is validated over the –40°C to +105°C temperature range specified for the MCF51AC256BVPUE.

Does the MCF51AC256BVPUE include a CAN controller?

No, the MCF51AC256BVPUE does not include a CAN controller. The 'B' in the part number explicitly denotes the CAN-disabled variant, confirmed in Table 1 of the Rev.7 datasheet and by the absence of TxCAN/RxCAN functionality in its pinout. For CAN support, use the 'A' variant such as MCF51AC256AVPUE.

What package type and dimensions does the MCF51AC256BVPUE use?

The MCF51AC256BVPUE uses a 64-pin LQFP package measuring 10 mm × 10 mm with 0.5 mm lead pitch. Mechanical details, including land pattern and thermal pad specifications, are defined in Freescale document MCF51AC256 Rev.7, Section 3 "Mechanical Outline Drawings" and Table 22.

How much flash and SRAM memory does the MCF51AC256BVPUE integrate?

The MCF51AC256BVPUE integrates 256 KB of on-chip flash memory and 32 KB of static RAM (SRAM). Both memory blocks are fully accessible across the device's operating voltage and temperature range, with flash supporting read/program/erase cycles and SRAM retaining data during low-power stop modes.

Which debug interface does the MCF51AC256BVPUE support?

The MCF51AC256BVPUE supports a single-wire background debug module (BDM) interface via the BKGD/MS pin. This interface provides full run-control, breakpoint setting, memory inspection, and real-time trace via the debug visibility bus (VBUS), all compliant with ColdFire V1 architecture requirements.