NXP Semiconductors MK51DX256CMC7

Overview

MK51DX256CMC7 from NXP Semiconductors (formerly Freescale) is a Kinetis K51-series ARM Cortex-M4 microcontroller with DSP extension, 256 KB on-chip flash, 128 KB RAM, and 72 MHz maximum CPU frequency. It operates from 1.71–3.6 V across –40 to +85°C ambient, integrates dual 16-bit SAR ADCs with PGA, USB OTG, five UARTs, and LCD controller - deployed in industrial HMI, portable medical devices, and smart sensor nodes.

For engineers reviewing the MK51DX256CMC7 datasheet, MK51DX256CMC7 pinout, MK51DX256CMC7 application, or MK51DX256CMC7 equivalent, key selection criteria include its 72 MHz Cortex-M4 core with FPU support, low-power stop modes down to 1.47 µA, integrated segment LCD driver (36×8 or 40×4), USB full/low-speed transceiver, and dual ADCs with programmable gain up to ×64 for precision analog front-end design.

Technical Context

The MK51DX256CMC7 implements a multi-clock architecture with three independent oscillators: 3–32 MHz main crystal oscillator, 32 kHz RTC crystal oscillator, and internal low-power oscillator (900–1100 µs period). Its MCG (Multipurpose Clock Generator) supports FEE, FEI, FBE, and BLPE modes to dynamically scale clock domains across performance and power states.

System-level integration includes an 8-channel motor control/PWM timer, two quadrature decoder timers, real-time clock with battery backup, hardware CRC engine, and 128-bit unique chip ID. Analog subsystem features two independent 16-bit SAR ADCs each with integrated PGA (×1 to ×64), 12-bit DAC, two op-amps, one transimpedance amplifier, and three comparators with embedded 6-bit DACs.

Key Specifications

Pinout & Package

Package: 121-pin MAPBGA (8 mm × 8 mm, MC suffix). Pinout validated per K51 Sub-Family Data Sheet Rev. 3, Section 8.2 "K51 Pinouts" - includes dedicated USB_DP/DM, multiple ADC input groups, LCD segment/backplane drivers, and configurable GPIO with digital filtering and slew rate control.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MK51DX256CMC7, MK51DN256CLL7 trades LCD/TSI capability for wider temperature range and QFP packaging, while MKE15Z256VLH7 shifts to Cortex-M0+ with CAN FD and safety features but removes USB and display interfaces - making MK51DX256CMC7 optimal for cost-sensitive, display-integrated industrial edge nodes.

Availability

MK51DX256CMC7 is available at Aetrix Electronics and suitable for industrial HMI, portable medical devices, and smart energy metering requiring stable component supply, long-term lifecycle assurance, and consistent MAPBGA-121 sourcing.

Supply support for MK51DX256CMC7 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, IoT, and mobile applications - formed through the merger of Freescale and NXP in 2015.

The MK51DX256CMC7 belongs to the Kinetis K51 microcontroller family, designed specifically for cost-optimized, low-power industrial human-machine interfaces and sensor-edge applications requiring integrated LCD, touch, USB, and precision analog peripherals.

FAQ

What is the maximum operating frequency of the MK51DX256CMC7?

The MK51DX256CMC7 supports a maximum system and core clock frequency of 72 MHz, achieved using the MCG in FEE mode with an external 3–32 MHz crystal. This delivers 115 DMIPS performance while maintaining compatibility with its 1.71–3.6 V supply range and –40 to +85°C operating temperature specification. The MK51DX256CMC7 sustains this frequency across all active power modes except VLPR, where core clock is limited to 4 MHz.

Does the MK51DX256CMC7 include a hardware floating-point unit (FPU)?

No, the MK51DX256CMC7 implements the ARM Cortex-M4 core with DSP extension but does not include a hardware floating-point unit. Its part number encoding ('D' in position 3) explicitly denotes "Cortex-M4 w/ DSP", whereas 'F' would indicate FPU inclusion. Signal processing tasks requiring floating-point math must use software libraries or fixed-point optimization - confirmed in the K51 Sub-Family Data Sheet Rev. 3, Section 2.3 "Fields".

What LCD configurations does the MK51DX256CMC7 support?

The MK51DX256CMC7's integrated segment LCD controller supports two configurations: up to 36 frontplanes and 8 backplanes, or 40 frontplanes and 4 backplanes - determined by package size and pin multiplexing. The MC package (121 MAPBGA) enables the full 36×8 configuration. It supports static, 1/2, 1/3, and 1/4 bias driving schemes and includes voltage boosting for operation below 3 V, as specified in Section 6.9.2 of the K51 Sub-Family Data Sheet.

How many ADC channels does the MK51DX256CMC7 provide, and what is their resolution?

The MK51DX256CMC7 integrates two independent 16-bit successive approximation register (SAR) ADCs - ADC0 and ADC1 - each with up to 16 configurable input channels. Both ADCs feature integrated programmable gain amplifiers (PGA) supporting gains from ×1 to ×64. Resolution remains 16 bits across all gain settings, with effective number of bits (ENOB) dependent on PGA configuration and signal chain noise - detailed in Section 6.6.1 of the K51 Sub-Family Data Sheet Rev. 3.

What is the lowest power consumption mode supported by the MK51DX256CMC7?

The MK51DX256CMC7 achieves its lowest active-retention power in Very-Low-Leakage Stop Mode 1 (VLLS1), drawing just 1.47 µA at –40 to +25°C with RTC running and 8 KB RAM retained. This mode disables the CPU, flash, and most clocks while preserving core registers, selected SRAM, and wake-up sources such as GPIO interrupts or RTC alarms - enabling ultra-long battery life in intermittent-sensing applications.