Nuvoton’s latest NuMicro M3331 series is a range of 32-bit Arm Cortex-M33 MCUs running at 180 MHz, incorporating an ARGB LED controller, DSP instruction set, single-precision FPU, and TrustZone security, designed for smart factories, renewable energy systems, and consumer devices.
Previously, we discussed other Cortex-M33 MCUs such as the STM32U3B5/C5, Texas Instruments MSPM33C321A, and Nordic Semi’s nRF54LM20A. The Nuvoton M3331, however, uniquely includes an Enhanced LED Light Strip Interface (ELLSI) and up to 10 standard LLSI channels, supporting gaming ARGB Gen1 and Gen2 LED protocols, efficiently managing dynamic LED effects. It consists of two variants: the M3333 series and the M3334 series; the latter features a high-speed USB 2.0 OTG controller with an integrated PHY.
NuMicro M3331 specifications:
– MCU core: Arm Cortex-M33 32-bit CPU @ 180 MHz with single-precision FPU, DSP instructions, and MPU
– Memory: Up to 320 KB SRAM, 64 KB with hardware parity check
– Storage: Up to 512 KB Dual Bank Flash memory (APROM) with ECC, 8 KB user-defined loader (LDROM), 1x SDH controller up to 45 Mbps, 1x Quad-SPI interface up to 45 MHz in Master mode, EBI i80 mode
– Peripherals: Up to 110 I/O pins with interrupts (M3334: up to 102), 1x USB High-Speed device/host/OTG controller (M3334 only), 1x I2S interface up to 12 Mbps, up to 3x SPI/I2S interfaces, up to 3x I2C interfaces with SMBus/PMBus support, 1x I3C interface, up to 2x CAN FD interfaces, up to 5x UART interfaces, up to 2x USCI (configurable as UART, SPI, or I2C)
– Timers and DMA: 4x 32-bit timers, 1x 24-bit SysTick timer, RTC, 1x WDT, 1x WWDT, 1x Enhanced Input Capture Unit (ECAP), 16-channel PDMA
– LED and motor control: Enhanced LED Light Strip Interface (ELLSI) and up to 10x LLSI, up to 28x PDCI channels, 48x PWM channels, 1x Enhanced Quadrature Encoder Interface (EQEI)
– Analog peripherals: 1x 12-bit SAR ADC with up to 16 channels and 4.2 Msps, 2x analog comparators, built-in internal reference voltage, temperature sensor, LVR, and BOD
– Security: TrustZone technology, secure boot (ROT), Flash memory with 4 regions of Execute-Only-Memory, 2 Kbytes of OTP ROM, 96-bit UID and 128-bit UCID
– Clocks: Internal PLL up to 180 MHz, 48 MHz RC oscillator, 38.4 kHz RC oscillator, crystal oscillators
– Power: Operating voltage 1.7V to 3.6V; consumption: Run – 91 μA/MHz, NPD2 – 190 μA, SPD – 4.93 μA, DPD – 0.62 μA
– Packages: QFN33, QFN48, LQFP48, LQFP64, LQFP128 (Halogen-free, RoHS, TSCA-compliant)
– Temperature Range: -40°C to +105°C
The company refers to these as the “NuMicro M3331 series” but mentions the M3333 and M3334 as subseries, creating some confusion. They offer NuMaker-M3333KI and NuMaker-M3334KI evaluation boards featuring Arduino UNO-compatible headers, detachable Nu-Link2-Me module, and dedicated ammeter connector. Software support includes a BSP and sample code compatible with Arm Keil MDK, IAR EWARM, Visual Studio Code, and real-time OS like FreeRTOS, Zephyr, RT-Thread, as well as GUI libraries emWin and LVGL.
The MCUs are not yet available for sale, but evaluation boards can be purchased for $30.00 each on Nuvoton Direct eStore. More details and documentation are on Nuvoton’s M3333 and M3334 series product pages.