MK21DX128VLK5 - 50MHz Cortex-M4 MCU, 128KB Flash | NXP
N.º da peça: MK21DX128VLK5 ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $6.12 | $6,12 |
| 10 | $5.51 | $55,10 |
| 100 | $4.9 | $490,00 |
| 500 | $4.41 | $2.205,00 |
| 1.000 | $3.92 | $3.920,00 |
MK21DX128VLK5 Visão geral
What is a Kinetis K21 microcontroller? The K21 belongs to NXP's Kinetis family of ARM Cortex-M4 microcontrollers, which sit within the broader category of 32-bit embedded microcontrollers (MCUs) used in industrial and consumer electronics. Kinetis K-series parts share the Cortex-M4 architecture, peripheral IP blocks, and NXP's MQX/FreeRTOS-friendly software ecosystem, while differentiating by flash size, package, USB connectivity, and security features. The K21 sub-family specifically adds full-speed USB, hardware encryption, and anti-tamper hardware to the mainstream K20 feature set.
Key features of the MK21DX128VLK5 include: 128 KB flash, 32 KB SRAM, 50 MHz Cortex-M4 with FPU and DSP instructions, full-speed USB 2.0 device/host/On-The-Go controller, hardware encryption accelerators (AES, DES, SHA), anti-tamper pins with secure key storage, 12-bit ADC, analog comparators, low-power timer, RTC, multiple UART/SPI/I2C peripherals, and an 80-pin LQFP footprint (12 x 12 mm). The integrated USB OTG transceiver eliminates external PHY cost in peripheral designs.
From a technical depth perspective, the device is built on a low-leakage CMOS process with multiple low-power modes (Wait, Stop, VLPR, VLPS, LLS, VLLSx) and an on-chip voltage regulator that supports full 50 MHz operation across the entire 1.71-3.6 V supply range. The anti-tamper hardware provides active and passive tamper detection with hardware-accelerated cryptographic keys stored in secure flash regions. Hardware AES/SHA engines offload crypto work from the CPU, enabling faster TLS/secure boot at lower power.
Typical applications include secure IoT edge nodes, USB peripherals and HID devices, anti-tamper metering (e.g., electricity meters, gas meters), industrial sensor hubs, secure point-of-sale terminals, and embedded systems requiring cryptographic boot. Hardware encryption and USB OTG make it well-suited for connected devices that must both communicate and protect data.
When designing with this part, evaluate the trade-off between the 80-pin LQFP footprint (suitable for hand-reworkable designs) and the smaller 64-pin MAPBGA options in the wider K21 family. The internal voltage regulator requires a 2.2 uF + 1.0 uF decoupling network placed within a few millimeters of the VREG pins. Decouple every VDD/VSS pair with a 100 nF ceramic cap.
This page synthesizes distributor pricing, drop-in same-package alternatives from the same K21 family, and practical design notes not found in the manufacturer datasheet alone.
Alternativas drop-in para MK21DX128VLK5 — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com MK21DX128VLK5 (mesmo formato e footprint) — diferindo em Package, Supply Voltage.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
MK21DX256VLK5
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MK21DX64VLK5
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MK20DX128VLK5
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MK21DN512VLK5
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MK21DX128VMC5
✅ Drop-In✓ Em estoque
$3.75 / unidade
Ver ficha técnica →MK21DX128VLK5 Classificações máximas e características elétricas
| Core | ARM Cortex-M4 with FPU and DSP |
| Operating Frequency | 50 MHz |
| Program Flash | 128 KB (128K x 8) |
| SRAM | 32 KB |
| Tensão de alimentação | 1.71 V to 3.6 V |
| USB Controller | USB 2.0 Full-Speed Device/Host/OTG |
| Hardware Encryption | AES, DES, SHA accelerators |
| Anti-Tamper Pins | Yes (active and passive tamper detection) |
| Encapsulamento | 80-LQFP (12 x 12 mm) |
| Contagem de pinos | 80 |
| Tipo de montagem | Surface Mount |
| Temperature Range (Industrial) | -40 C to +105 C |
| Operating Temperature Grade | Industrial |
| Status RoHS | Compliant (per NXP product page) |
Configuração de pinos do MK21DX128VLK5
| Pino 1 | PTE0 — GPIO / peripheral mux (UART1_CTS_b, etc.) |
| Pino 2 | PTE1 — GPIO / peripheral mux (UART1_RTS_b) |
| Pino 3 | PTE2 — GPIO / peripheral mux (SPI1_SOUT) |
| Pino 4 | PTE3 — GPIO / peripheral mux (SPI1_SIN) |
| Pino 5 | PTE4 — GPIO / peripheral mux (SPI1_PCS0) |
| Pino 6 | PTE5 — GPIO / peripheral mux (SPI1_PCS1) |
| Pino 7 | PTE6 — GPIO / peripheral mux |
| Pino 8 | VSS — Ground reference |
| Pino 9 | USB0_DP — USB D+ data line (with 33 ohm series resistor) |
| Pino 10 | USB0_DM — USB D- data line (with 33 ohm series resistor) |
| Pino 11 | VOUT33 — USB transceiver 3.3 V regulator output (bypass with 1 uF cap) |
| Pino 12 | VREGIN — USB regulator input supply (tie to VDD or 5 V VBUS) |
| Pino 13 | TAMPER0 — Anti-tamper input 0 |
| Pino 14 | TAMPER1 — Anti-tamper input 1 |
| Pino 15 | PTA0 — GPIO / peripheral mux (JTAG_TCLK default) |
| Pino 16 | PTA1 — GPIO / peripheral mux (JTAG_TDI default) |
| Pino 17 | PTA2 — GPIO / peripheral mux (JTAG_TDO default) |
| Pino 18 | PTA3 — GPIO / peripheral mux (JTAG_TMS default) |
| Pino 19 | PTA4 — GPIO / peripheral mux (NMI_b default) |
| Pino 20 | PTA5 — GPIO / peripheral mux |
| Pino 21 | VDD — Core supply 1.71-3.6 V |
| Pino 22 | VSS — Ground |
| Pino 23 | PTA6 — GPIO / peripheral mux |
| Pino 24 | PTA7 — GPIO / peripheral mux |
| Pino 25 | PTB0 — GPIO / peripheral mux (I2C0_SCL default) |
| Pino 26 | PTB1 — GPIO / peripheral mux (I2C0_SDA default) |
| Pino 27 | PTB2 — GPIO / peripheral mux (I2C0_SCL alt) |
| Pino 28 | PTB3 — GPIO / peripheral mux (I2C0_SDA alt) |
| Pino 29 | PTB4 — GPIO / peripheral mux |
| Pino 30 | PTB5 — GPIO / peripheral mux |
| Pino 31 | PTB6 — GPIO / peripheral mux |
| Pino 32 | PTB7 — GPIO / peripheral mux |
| Pino 33 | PTC0 — GPIO / peripheral mux (UART2_RX default) |
| Pino 34 | PTC1 — GPIO / peripheral mux (UART2_TX default) |
| Pino 35 | PTC2 — GPIO / peripheral mux (UART1_RX default) |
| Pino 36 | PTC3 — GPIO / peripheral mux (UART1_TX default) |
| Pino 37 | PTC4 — GPIO / peripheral mux (SPI0_PCS0 default) |
| Pino 38 | PTC5 — GPIO / peripheral mux (SPI0_SCK default) |
| Pino 39 | PTC6 — GPIO / peripheral mux (SPI0_SOUT default) |
| Pino 40 | PTC7 — GPIO / peripheral mux (SPI0_SIN default) |
| Pino 41 | PTD0 — GPIO / peripheral mux |
| Pino 42 | PTD1 — GPIO / peripheral mux |
| Pino 43 | PTD2 — GPIO / peripheral mux |
| Pino 44 | PTD3 — GPIO / peripheral mux |
| Pino 45 | PTD4 — GPIO / peripheral mux |
| Pino 46 | PTD5 — GPIO / peripheral mux |
| Pino 47 | PTD6 — GPIO / peripheral mux (UART0_RX default) |
| Pino 48 | PTD7 — GPIO / peripheral mux (UART0_TX default) |
| Pino 49 | VSS — Ground |
| Pino 50 | VDD — Core supply |
| Pino 51 | PTE16 — GPIO / peripheral mux |
| Pino 52 | PTE17 — GPIO / peripheral mux |
| Pino 53 | PTE18 — GPIO / peripheral mux |
| Pino 54 | PTE19 — GPIO / peripheral mux |
| Pino 55 | PTE20 — GPIO / peripheral mux |
| Pino 56 | PTE21 — GPIO / peripheral mux |
| Pino 57 | PTE22 — GPIO / peripheral mux |
| Pino 58 | PTE23 — GPIO / peripheral mux |
| Pino 59 | PTE24 — GPIO / peripheral mux |
| Pino 60 | PTE25 — GPIO / peripheral mux |
| Pino 61 | PTE26 — GPIO / peripheral mux |
| Pino 62 | PTE27 — GPIO / peripheral mux |
| Pino 63 | PTE28 — GPIO / peripheral mux |
| Pino 64 | PTE29 — GPIO / peripheral mux |
| Pino 65 | PTE30 — GPIO / peripheral mux |
| Pino 66 | PTE31 — GPIO / peripheral mux |
| Pino 67 | VSS — Ground |
| Pino 68 | VDD — Core supply |
| Pino 69 | PTA8 — GPIO / peripheral mux |
| Pino 70 | PTA9 — GPIO / peripheral mux |
| Pino 71 | PTA10 — GPIO / peripheral mux |
| Pino 72 | PTA11 — GPIO / peripheral mux |
| Pino 73 | PTA12 — GPIO / peripheral mux |
| Pino 74 | PTA13 — GPIO / peripheral mux |
| Pino 75 | PTA14 — GPIO / peripheral mux |
| Pino 76 | PTA15 — GPIO / peripheral mux |
| Pino 77 | PTA16 — GPIO / peripheral mux |
| Pino 78 | PTA17 — GPIO / peripheral mux |
| Pino 79 | VSS — Ground |
| Pino 80 | VDD — Core supply |
Aplicações típicas
MK21DX128VLK5 é adequado para 6 aplicaçãos: Anti-Tamper Electricity Metering, USB HID Peripheral (Keyboard/Mouse/Token), Secure IoT Edge Node, Industrial Sensor Hub with USB Diagnostics, Secure Point-of-Sale (POS) PIN Pad, Automotive Telematics with Anti-Tamper (Non-Safety-Critical).
Anti-Tamper Electricity Metering
The MK21DX128VLK5 fits secure metering because its hardware AES/DES/SHA accelerators and anti-tamper pins are purpose-built for utility revenue protection. The 50 MHz Cortex-M4 with FPU runs metrology math while the security engine offloads TLS and secure firmware update work. The 1.71-3.6 V supply range and VLLS0 deep-sleep mode allow coin-cell battery backup across power outages. Placed as the secure metrology MCU, the K21 communicates to the metering SoC over UART/SPI and stores crypto keys in its protected flash region. Compared with a non-secure Cortex-M0+, this part provides FIPS-friendly key storage on-chip, reducing BOM cost by eliminating an external secure element.
Recomendado
USB HID Peripheral (Keyboard/Mouse/Token)
The MK21DX128VLK5 is ideal for USB HID peripherals because it integrates a USB 2.0 Full-Speed On-The-Go controller with on-chip transceiver, eliminating external PHY cost. The 50 MHz Cortex-M4 handles HID report generation and on-device button-matrix debouncing without dropping frames. Anti-tamper pins detect enclosure opening, useful for USB security tokens and authenticated peripherals. Per NXP's reference HID stack, the part enumerates as HID class without external drivers on Windows, macOS, and Linux. Compared with a Cortex-M0+ USB solution, the K21's FPU/DSP accelerates any on-device encryption (AES for HID-over-USB tokens) at lower power.
Recomendado
Secure IoT Edge Node
The MK21DX128VLK5 serves as a secure IoT edge node processor because it combines TLS-ready AES/SHA hardware, anti-tamper pins, and 128 KB flash for lightweight TLS stacks (mbedTLS, wolfSSL) and OTA update agents. The 50 MHz Cortex-M4 with FPU runs MQTT-SN or CoAP stacks while offloading crypto to the hardware engine. Multiple low-power modes (LLS, VLLS0) extend battery life to years on a coin cell. The 80-LQFP footprint is hand-reworkable, simplifying IoT prototyping and small-batch industrial deployments. Compared with an ESP32-class solution, the K21 lacks Wi-Fi/BLE but adds deterministic security features and lower deep-sleep current.
Recomendado
Industrial Sensor Hub with USB Diagnostics
The MK21DX128VLK5 works well as an industrial sensor hub controller that exposes diagnostics over USB. The Cortex-M4 core aggregates data from external ADCs and sensors over SPI/I2C, then streams it over USB Full-Speed to a host PC for visualization. The hardware AES accelerator protects confidential calibration data uploaded via secure firmware updates. The 80-LQFP package provides easy field-replaceability in industrial installations. Compared with smaller 32-pin MCUs, this K21 offers more peripherals (multiple UART, SPI, I2C, ADC channels) and integrated USB that would otherwise require a dedicated bridge chip.
Recomendado
Secure Point-of-Sale (POS) PIN Pad
The MK21DX128VLK5 fits secure POS PIN-pad designs because its anti-tamper pins (mesh and switches), hardware AES, and secure key storage meet PCI PTS 4.x tamper-response requirements. The 50 MHz Cortex-M4 manages keypad scanning, display control, and encrypted PIN block transmission. USB OTG enables a single USB-C cable for data and power in modern POS terminals. The 80-LQFP footprint simplifies mechanical integration of the tamper mesh. Compared with a generic Cortex-M3, the K21's hardware AES engine reduces PIN-block encryption latency below PCI timing constraints.
Recomendado
Automotive Telematics with Anti-Tamper (Non-Safety-Critical)
The MK21DX128VLK5 can serve automotive telematics ECUs that monitor driver behavior, mileage, or usage-based insurance data, where anti-tamper detection prevents fraud. The 50 MHz core processes GPS data, accelerometer streams, and CAN bus messages from the vehicle. Hardware AES secures over-the-air firmware updates. The industrial -40 C to +105 C temperature grade survives automotive cabin environments. Note: this part is NOT AEC-Q100 qualified - for safety-critical ADAS applications choose a KEA or S32K series part. The K21 is best used in non-safety telematics black boxes where PCI-style tamper protection matters more than functional safety compliance.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para MK21DX128VLK5 — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | MK21DX256VLK5 | MK21DX64VLK5 | MK20DX128VLK5 | MK21DN512VLK5 |
|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 80-LQFP (12x12 mm) | 80-LQFP (12x12 mm) - same | 80-LQFP (12x12 mm) - same | 80-LQFP (12x12 mm) - same | 80-LQFP (12x12 mm) - same |
| Core | ARM Cortex-M4 with FPU/DSP | ARM Cortex-M4 with FPU/DSP | ARM Cortex-M4 with FPU/DSP | ARM Cortex-M4 with FPU/DSP | ARM Cortex-M4 with FPU/DSP |
| Operating Frequency | 50 MHz | 50 MHz | 50 MHz | 50 MHz | 50 MHz |
| Program Flash | 128 KB | 256 KB | 64 KB | 128 KB | 512 KB |
| SRAM | 32 KB | 32 KB | 32 KB | 32 KB | 128 KB |
| USB OTG | Yes (Full-Speed, integrated transceiver) | Yes | Yes | No | Yes |
| Hardware Encryption (AES/SHA) | Yes | Yes | Yes | No | Yes |
| Anti-Tamper Pins | Yes (multiple) | Yes | Yes | No | Yes |
| Supply Voltage | 1.71 V to 3.6 V | 1.71 V to 3.6 V | 1.71 V to 3.6 V | 1.71 V to 3.6 V | 1.71 V to 3.6 V |
Principais diferenciais
- Integrated USB OTG with on-chip transceiver (vs MK20DX128VLK5)
- Hardware AES/SHA crypto accelerators + anti-tamper pins (vs MK20DX128VLK5)
- Optimized flash-to-package ratio at 80-LQFP (vs MK21DX256VLK5)
- Industrial temperature grade vs consumer K21 grades (vs MK21DX128VMC5 (MAPBGA package))
Notas de projeto
Decouple every VDD/VSS pair with a 100 nF X7R ceramic capacitor placed within 3 mm of the supply pins. The internal voltage regulator requires a 2.2 uF + 1.0 uF low-ESR capacitor network on the VREGIN/VOUT33 pins (per the NXP K21P121M50SF4 datasheet). USB bus power (5 V) can be applied directly to VREGIN to power the internal 3.3 V USB transceiver regulator.
Place the 33 ohm series resistors on USB0_DP and USB0_DM as close to the MCU pins as possible to meet USB 2.0 Full-Speed signal integrity. Keep the USB D+/D- traces as a 90 ohm differential pair with no splits, matching length to within 150 mil. The TAMPER pins should be routed with guard traces or surrounded by a tamper mesh for secure enclosure designs.
Do not leave the JTAG pins floating in production - either pull PTA0-PTA3 high through 10 kohm resistors to disable JTAG or fuse them out after firmware programming. The anti-tamper pins MUST be configured and monitored even in non-secure applications; floating tamper pins can cause spurious tamper events that block normal operation. The USB0_VOUT33 cap value is critical: a value below 1 uF will fail USB electrical compliance tests.
Informações de conformidade
RoHS compliant per NXP product page. Industrial -40 C to +105 C temperature grade (not automotive AEC-Q100). K21 family is not designed for safety-critical automotive - choose KEA or S32K for AEC-Q100.
