Kinetis® K51-72 MHz, Segment LCD, USB Microcontrollers (MCUs) based on Arm® Cortex®-M4 Core

Click over video to play

Block Diagram

Kinetis K51 Mid-Performance MCUs Block Diagram

Kinetis K51 Mid-Performance MCUs Block Diagram



  • 10 low-power modes with power and clock gating for optimal peripheral activity and recovery times. Stop currents of <1.45 µA run currents of <277µA/MHz, 4µs wake-up from stop mode
  • Full memory and analog operation down to 1.71 volts for extended battery life
  • Low-leakage wake-up unit with up to eight internal modules and 16 pins as wake-up sources in low-leakage stop (LLS)/very low-leakage stop (VLLS) modes
  • Low-power timer for continual system operation in reduced power state

Flash, SRAM and FlexMemory

  • 128 KB-256 KB flash. Fast access, high reliability with four-level security protection
  • 32 KB-64 KB of SRAM
  • FlexMemory: 2 KB of user-segmentable byte write/erase EEPROM for data tables/system data. EEPROM with over 10M cycles and flash with 70 µsec write time (brownouts without data loss or corruption). No user or system intervention to complete programming and erase functions and full operation down to 1.71 volts. In addition, 32 KB FlexNVM for extra program code, data or EEPROM backup

Mixed-Signal Capability

  • Up to two operational amplifiers allow signal filtering and amplification
  • One transimpedance amplifier optimized for converting current inputs into voltages that can be read by the ADC
  • Up to two high-speed 16-bit ADCs with configurable resolution. Single or differential output mode operation for improved noise rejection. 500 ns conversion time achievable with programmable delay block triggering
  • One 12-bit DACs for analog waveform generation for medical applications baseline (glucometer, pulseoximeter)
  • Up to three high-speed comparators providing fast and accurate motor over-current protection by driving PWMs to a safe state
  • Up to two programmable gain amplifiers with x64 gain for small amplitude signal conversion
  • Analog voltage reference provides an accurate reference to analog blocks, ADC and DAC, and replaces external voltage references to reduce system cost


  • Cortex-M4 core + DSP.
  • 72 MHz, single cycle MAC, single instruction multiple data (SIMD) extensions
  • 16-channel DMA for peripheral and memory servicing with reduced CPU loading and faster system throughput
  • Cross bar switch enables concurrent multi-leader bus accesses, increasing bus bandwidth
  • Independent flash banks allow concurrent code execution and firmware updating with no performance degradation or complex coding routines

Timing and Control

  • FlexTimer with a total of eight channels. Hardware dead-time insertion and quadrature decoding for motor control
  • Carrier modulator timer for infrared waveform generation in remote control applications
  • Four-channel 32-bit periodic interrupt timer provides time base for RTOS task scheduler or trigger source for ADC conversion and programmable delay block

Human-Machine Interface

  • Hardware touch-sensing interface with up to 16 inputs. Operates in all low power modes (minimum current adder when enabled). Hardware implementation avoids software polling method. High sensitivity level allows use of overlay surfaces upto 5 mm thick
  • Flexible, low-power LCD controller with up to 288 segments (36x8 or 40x4). LCD blink mode enables low average power while remaining in low-power mode. Segment fail detect guards against erroneous readouts and reduces LCD test costs. Frontplane/backplane reassignment provides pin-out flexibility easing PCB design and allows LCD configuration changes via firmware with no hardware re-work. Supports multiple 3-volt and 5-volt LCD panel sizes with fewer segments (pins) than competitive controllers and no external components. Unused LCD pins can be configured as other GPIO functions

Connectivity and Communications

  • USB 2.0 OTG (full speed). Device charge detect optimizes charging current/time for portable USB devices enabling longer battery life. Low-voltage regulator supplies up to 120 mA off chip at 3.3 volts to power external components from 5-volt input
  • Up to five UARTs with IrDA support including one UART with ISO7816 smart card support. Variety of data size, format and transmission/reception settings supported for multiple industrial communication protocols
  • Inter-IC Sound (I²S) serial interface for audio system interfacing
  • Up to two DSPI and two I²C

Reliability, Safety and Security

  • Cyclic redundancy check engine validates memory contents and communication data, increasing system reliability
  • Independent-clocked COP guards against clock skew or code runaway for fail-safe applications such as the IEC 60730 safety standard for household appliances
  • External watchdog monitor drives output pin to safe state external components if watchdog event occurs
  • This product is included in NXP®.s product longevity program, with assured supply for a minimum of 10 years after launch

Part numbers include: MK51DX128CLH7, MK51DX128CLK7, MK51DX128CMC7, MK51DX256CLK7, MK51DX256CLL7, MK51DX256CMC7.


Quick reference to our documentation types.

1-5 of 77 documents

Show All

Design Files

Quick reference to our design files types.

2 design files

  • Symbols and Footprints

    Kinetis® Symbols, Footprints and Models

  • Calculators

    TFS FlexMem Endurance Calculator


Quick reference to our board types.

1-5 of 10 hardware offerings

Show All


Quick reference to our software types.

1-5 of 9 software files

Show All

Note: For better experience, software downloads are recommended on desktop.

Engineering Services

1-5 of 14 engineering services

Show All

To find additional partner offerings that support this product, visit our Partner Marketplace.


5 trainings