Kinetis K21-120 MHZ, Full-Speed USB, Anti-Tamper Microcontrollers based on Arm® Cortex®-M4

K21_120

The Kinetis K21 120 MHz MCU family targets cost-sensitive applications requiring low-power functionality.

  • Features hardware encryption and tamper detection
  • Includes a rich suite of analog, communication, timing and control peripherals to accommodate a wide range of requirements
  • Maximizes board space and enhances performance with minimum-length interconnections
  • Provides performance efficiency with low power
  • Delivers significant BOM savings through smart on-chip integration
  • Shares the comprehensive enablement and scalability of the Kinetis portfolio

Please contact your local NXP representative to download the K21 Security Data sheet and Reference Manual documents (under NDA).

Block Diagram

Kinetis K21 MCU Family Block Diagram

Kinetis K21 MCU Family Block Diagram
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Features

Ultra-Low-Power

  • 10 low-power modes with power and clock gating for optimal peripheral activity and recovery times. Stop currents of <500 nA, run currents of <200 µA/MHz, 4 µs 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

  • 512 KB-1 MB flash. Fast access, high reliability with four-level security protection
  • 128 KB of SRAM
  • FlexMemory: 32 bytes-16 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/corruption). No user or system intervention to complete programming and erase functions and full operation down to 1.71 volts. In addition, 128 KB of FlexNVM for extra program code, data or EEPROM backup

Mixed-Signal capability

  • Up to two high-speed, 16-bit analog-to-digital converters (ADCs) with configurable resolution. Single or differential output mode operation for improved noise rejection. 500 ns conversion time achievable with programmable delay block triggering
  • Up to two 12-bit digital-to-analog converters (DACs) for analog waveform generation for audio applications
  • Up to three high-speed comparators providing fast and accurate motor over-current protection by driving PWMs to a safe state
  • Analog voltage reference provides an accurate reference to analog blocks, ADC and DAC, and replaces external voltage references to reduce system cost

Performance

  • Arm® Cortex-M4® core + DSP. 120 MHz, single cycle MAC, single instruction multiple data (SIMD) extensions, single precision floating point unit
  • Up to 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

  • Up to four FlexTimers with a total of 20 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 (HMI)

  • Up to 16 controllable GPIO with pin interrupt support

Connectivity and Communications

  • USB 2.0 On-The-Go (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 volts input
  • Up to six 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
  • CAN module for industrial network bridging
  • Up to three DSPI and two I2C

Security

  • Hardware Encryption coprocessor for secure data transfer and storage. Faster than software implementations and with minimal CPU loading. Supports a wide variety of algorithms - DES, 3DES, AES, MD5, SHA-1, SHA-256
  • System security and tamper detect with secure real-time clock with independent battery supply. Secure key storage with internal/external tamper detect for unsecure flash, temperature, clock, and supply voltage variations and physical attack detection

Reliability, Safety and Security

  • Memory protection unit provides memory protection for all leaders on the cross bar switch, increasing software reliability
  • 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

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  • Symbols and Footprints

    Kinetis® Symbols, Footprints and Models

    INTERNALRev 1.0Nov 27, 2017 11:23:001 KBCAD-SYMBOLFOOTPRINTS
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  • Calculators

    Kinetis® Power Estimation Tool

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  • Calculators

    TFS FlexMem Endurance Calculator

    ZIPRev vBeta025Aug 1, 2014 00:00:003.2 MBTFS_FLEXMEM_CALCULATOR
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