NXP Semiconductors MK21FX512VMC12

Overview

MK21FX512VMC12 from NXP (formerly Freescale) is a 120 MHz ARM Cortex-M4-based microcontroller with FPU, optimized for cost-sensitive, low-power applications requiring USB OTG connectivity and robust tamper detection-such as electronic point-of-sale terminals. It integrates 512 KB flash, 128 KB SRAM, DryIce tamper monitoring, and operates from 1.71–3.6 V across –40 to 105°C.

For engineers reviewing the MK21FX512VMC12 datasheet, MK21FX512VMC12 pinout, MK21FX512VMC12 application, or MK21FX512VMC12 equivalent, this page delivers verified specifications including USB 2.0 OTG compliance, dual 16-bit ADCs, CAN 2.0B interface, FlexTimers for motor control, and ultra-low static power down to 268 nA in VLLS0 mode with POR detect disabled.

Technical Context

The MK21FX512VMC12 implements an ARM Cortex-M4 core with hardware floating-point unit and DSP extensions, delivering 1.25 Dhrystone MIPS/MHz. Its clock system includes PLL, FLL, and multiple internal oscillators supporting dynamic frequency scaling from 4 MHz (VLPR) to 120 MHz (RUN), with dedicated USB clock domain requiring ≥20 MHz system clock during FS operation.

Security architecture centers on DryIce tamper detection-monitoring active/passive pins, temperature, supply voltage, and clock integrity-with secure storage, hardware RNG, AES encryption, and 128-bit unique chip ID. Memory subsystem comprises 512 KB program flash, 128 KB SRAM, and optional FlexMemory (not present in FX variant), managed by MPU and 16-channel DMA.

Key Specifications

Pinout & Package

Package: 121-pin MAPBGA, 8 mm × 8 mm × 1.4 mm, 0.65 mm pitch. Thermal resistance: 36°C/W (4-layer board).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MK21FX512VMC12, MK21FN1M0VMC12 offers seamless flash capacity expansion within identical footprint and power profile, while MK64FX512VLQ12 trades USB-centric optimization for Ethernet capability at the cost of package incompatibility and higher static power.

Availability

MK21FX512VMC12 is available at Aetrix Electronics and suitable for electronic point-of-sale systems, industrial HMI terminals, and smart energy meters requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for MK21FX512VMC12 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 ARM-based microcontrollers from its Freescale acquisition.

The MK21FX512VMC12 belongs to the Kinetis K21F sub-family, designed specifically for cost-optimized, tamper-resistant embedded applications demanding USB OTG, low-power operation, and cryptographic security - targeting EPOS, secure metering, and industrial control.

FAQ

What is the maximum operating frequency of the MK21FX512VMC12 core?

The MK21FX512VMC12 features an ARM Cortex-M4 core with FPU rated for up to 120 MHz operation. This frequency is achievable under PEE (PLL Engaged External) clock mode with appropriate voltage (≥2.7 V) and thermal conditions. At lower supply voltages (1.71–2.7 V), maximum core frequency is reduced per electrical specifications in the datasheet.

Does the MK21FX512VMC12 include an integrated USB voltage regulator?

Yes, the MK21FX512VMC12 integrates a 3.3 V, 120 mA LDO regulator dedicated to the USB PHY. This allows fully self-contained USB operation without external regulation - critical for compact EPOS and portable industrial devices where board space is constrained.

What low-power modes does the MK21FX512VMC12 support, and what is the lowest current draw?

The MK21FX512VMC12 supports seven low-power modes, including VLLS0 (Very-Low-Leakage Stop 0). With POR detect circuit disabled, VLLS0 draws just 268 nA at 3.0 V and –40 to 25°C - enabling decade-scale battery life for RTC and tamper monitoring in always-on applications.

Is the MK21FX512VMC12 pin-compatible with other Kinetis K21 devices?

Yes, the MK21FX512VMC12 shares the same 121-pin MAPBGA package and pinout with MK21FN1M0VMC12. This enables direct replacement for flash capacity upgrades without PCB modification - confirmed by Freescale's K21F family pin assignment documentation.

What security features are implemented in the MK21FX512VMC12 for tamper protection?

The MK21FX512VMC12 implements DryIce tamper detection, monitoring supply voltage, temperature, clock integrity, and active/passive pins. Upon violation, it triggers secure memory erase, disables debug interfaces, and asserts tamper flags - meeting EPOS anti-tampering requirements per PCI PTS v5.x standards.