NXP Semiconductors MCF51MM256CLK

Overview

MCF51MM256CLK from NXP Semiconductors (formerly Freescale) is a 32-bit ColdFire V1 microcontroller with 256 KB Flash, 32 KB RAM, and integrated measurement engine including 16-bit ADC, 12-bit DAC, dual op-amps, and trans-impedance amplifiers. It operates up to 50.33 MHz at >2.4 V, supports USB On-The-Go, Mini-FlexBus, and ultra-low-power stop modes down to 6 µs wake-up - deployed in handheld metering and portable instrumentation.

For engineers reviewing the MCF51MM256CLK datasheet, MCF51MM256CLK pinout, MCF51MM256CLK application, or MCF51MM256CLK equivalent, key selection criteria include its ColdFire ISA_C CPU core, dual 128 KB Flash arrays enabling concurrent execution/programming, integrated TOD timer with 32.768 kHz XOSC1, MCG PLL/FLL clock generation with ±0.5% to –1% deviation over voltage/temperature, and 104-pin MAPBGA package with dedicated infrared output (IRO) and rapid GPIO support.

Technical Context

The MCF51MM256CLK implements the ColdFire V1 CPU core with ISA_C instruction set, supporting 32-bit MAC operations for signed/unsigned integer and fractional arithmetic. Its Multipurpose Clock Generator (MCG) integrates both PLL and FLL, with internal reference trimming enabling 0.2% resolution and typical ±0.75% accuracy across –40°C to 105°C.

It features two independent 128 KB Flash arrays allowing interrupt servicing during programming, hardware CRC acceleration, and a programmable delay block (PDB) that synchronizes ADC sampling and DAC output with precise trigger timing - critical for sensor biasing and high-fidelity analog acquisition in battery-powered devices.

Key Specifications

Pinout & Package

Package: 104-pin MAPBGA (10 mm × 10 mm). Pin count and function mapping confirmed per Freescale Document MCF51MM256 Rev. 5, Section 2.1 and Table 3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Kinetis K22FN512 and RA4M1 Group, the MCF51MM256CLK delivers unique on-die analog signal conditioning (TRIAMP, 16-bit ADC, 12-bit DAC, PDB synchronization) and ColdFire deterministic real-time performance - making it irreplaceable in compact, battery-operated metering where analog integration reduces BOM and layout complexity.

Availability

MCF51MM256CLK is available at Aetrix Electronics and suitable for handheld energy meters, portable gas analyzers, smart water quality monitors, and infrared remote control hubs requiring stable component supply and long-term industrial availability.

Supply support for MCF51MM256CLK 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 markets, with deep heritage in microcontrollers and analog integration.

The MCF51MM256CLK belongs to the ColdFire V1 MCU family, designed specifically for low-cost, low-power, high-precision handheld metering and portable instrumentation - emphasizing integrated analog front-ends, ultra-low-power operation, and robust real-time control.

FAQ

What is the maximum operating frequency of the MCF51MM256CLK and under what voltage conditions?

The MCF51MM256CLK achieves up to 50.33 MHz when supplied above 2.4 V, 40 MHz above 2.1 V, and 20 MHz above 1.8 V - all across the full industrial temperature range of –40°C to 105°C. This voltage-frequency scaling is enforced by internal regulators and verified in Freescale's MCF51MM256 Rev. 5 datasheet Section 3.5 (DC Characteristics) and Table 18 (MCG specifications).

Does the MCF51MM256CLK support simultaneous Flash read and program operations?

Yes, the MCF51MM256CLK contains two independent 128 KB Flash arrays, enabling concurrent execution from one array while programming or erasing the other - a capability confirmed in the "On-Chip Memory" section of the MCF51MM256 Rev. 5 datasheet. This allows uninterrupted interrupt handling during firmware updates.

How does the Programmable Delay Block (PDB) coordinate with the ADC and DAC in the MCF51MM256CLK?

The PDB in the MCF51MM256CLK generates precise, programmable trigger events to initiate ADC conversions and DAC updates - ensuring deterministic timing alignment between stimulus and measurement. As documented in Section "Measurement Engine PDB" of the datasheet, it supports back-to-back and timed modes, with 8 outputs dedicated to ADC channel triggering and sequence completion interrupts.

What analog peripherals are integrated into the MCF51MM256CLK beyond the ADC and DAC?

Beyond the 16-bit ADC and 12-bit DAC, the MCF51MM256CLK integrates two general-purpose op-amps (OPAMPx), two trans-impedance amplifiers (TRIAMPx), a programmable analog comparator (PRACMP), and voltage reference output (VREFO). These are explicitly listed in Table 2 ("Functional Units") and Figure 1 (Block Diagram) of the MCF51MM256 Rev. 5 datasheet.

Is the MCF51MM256CLK pin-compatible with other members of the MCF51MM series such as the MCF51MM128?

No - the MCF51MM256CLK is not pin-compatible with the MCF51MM128. While both share the same functional units, Table 1 ("Features by MCU and Package") confirms differing pin counts: MCF51MM256 supports 104-, 100-, 81-, and 80-pin packages, whereas MCF51MM128 is limited to 100-, 81-, and 80-pin variants. The 104-pin MAPBGA footprint is exclusive to the MCF51MM256CLK and enables additional Mini-FlexBus and analog I/O signals.