Item specifics
Description
STM32L431CCU6 Product Overview
STM32L431CCU6 is an Arm Cortex-M4 MCU at 80 MHz with FPU and ART Accelerator, UFQFPN-48. 256 KB Flash, 64 KB SRAM, USB 2.0 FS device (crystal-less), 12-bit ADC (10 ch), two 12-bit DACs, two comparators, LP timers, RTC, 2×USART, 1×UART, 1×LPUART, 2×SPI/I2S, 2×I2C. Up to 38 x 5 V-tolerant I/Os. 1.71–3.6 V, -40–85 °C. Compared to the LQFP-48 STM32L431CCT6, the STM32L431CCU6 uses a more compact UFQFPN-48 package, dramatically reducing PCB footprint while retaining the same 256 KB Flash, 64 KB SRAM, and rich peripherals, making the STM32L431CCU6 ideal for space-constrained battery-powered IoT nodes, portable devices, and sensor applications.
STM32L431CCU6 Core Features
Core: The STM32L431CCU6 features an Arm Cortex-M4 core at 80 MHz, with FPU + ART Accelerator
Memory: The STM32L431CCU6 provides 256 KB Flash and 64 KB SRAM (incl. 16 KB with HW parity), offering a balanced combination for embedded applications
USB: The STM32L431CCU6 integrates a USB 2.0 FS device (crystal-less)
Analog: 12-bit ADC (10 ch), 2×12-bit DACs, 2×Comparators
Connectivity: 2×USART, 1×UART, 1×LPUART, 2×SPI/I2S, 2×I2C
Timers: 1×Advanced Timer, multiple GP/LP timers, RTC
I/Os: 38 (5 V-tolerant)
Package: UFQFPN-48
Temperature Range: -40°C to 85°C
STM32L431CCU6 Applications
IoT Sensor Nodes: Battery-powered wireless sensors and USB data acquisition modules can leverage the STM32L431CCU6's low power and connectivity
Portable Devices: Wearables, portable medical devices, and USB peripherals benefit from the STM32L431CCU6's compact integration
Industrial Metering: Water, gas, and electricity meters are ideal applications for the STM32L431CCU6
Consumer Electronics: Remote controls, e-labels, smart cards
Space-Constrained Energy Harvesting: Self-powered sensor nodes and energy harvesting systems can rely on the STM32L431CCU6's ultra-low power consumption
STM32L431CCU6 Key Advantages
Cortex-M4 + FPU + Ultra-Low Power: The STM32L431CCU6 delivers excellent DSP and floating-point performance while maintaining extremely low power consumption
Integrated Crystal-less USB: The STM32L431CCU6 enables USB communication without an external crystal, simplifying design and saving BOM
256 KB Flash + 64 KB SRAM: The STM32L431CCU6 provides large storage for complex protocol stacks and data processing
Dual DACs + Dual Comparators: The STM32L431CCU6 offers flexible analog output and signal threshold detection without external components
LPUART Low-Power Serial Interface: Supports asynchronous communication in low-power modes, further optimizing system power consumption
Ultra-Compact UFQFPN-48 Package: Significantly reduces PCB area while retaining all peripherals
5 V-tolerant I/Os: Enhanced system noise immunity, simplified external level-shifting circuitry
Full Ecosystem Compatibility: Easy development with STM32CubeIDE/HAL/LL libraries for the STM32L431CCU6
Why Choose QIXINWEI
Years of experience in the electronics industry. Trusted by global customers.
Massive In-Stock Inventory – Ready to ship promptly.
BOM Matching Service – One-stop solution, save time.
PCBA Customization – Professional engineering team creates tailor-made solutions based on your needs.
Cost-Effective & Efficient – Better channel, better cost.
A dedicated team makes your procurement smoother.
Contact us for BOM quotes or PCBA inquiries.
FAQ
1. What is STM32L431CCU6?
STM32L431CCU6 is an ultra-low-power 32-bit MCU from STMicroelectronics' STM32L4 series, built around an Arm® Cortex®-M4 core with FPU and DSP in a UFQFPN-48 package (7 mm × 7 mm). Running at 80 MHz, the STM32L431CCU6 offers 256 KB Flash and 64 KB SRAM, along with USB OTG FS, high-precision 12-bit ADC/DAC, and rich low-power modes—providing a cost-effective platform for space- and power-constrained general-purpose battery-powered devices.
2. What are the key specifications of STM32L431CCU6?
Core: Arm® Cortex®-M4, up to 80 MHz, 100 DMIPS with FPU and DSP
Memory: 256 KB Flash, 64 KB SRAM
Operating Voltage: 1.71 V to 3.6 V
Temperature Range: -40 °C to +85 °C (industrial grade)
I/O Count: up to 38
Package: UFQFPN-48 (7 mm × 7 mm)
3. What are the characteristics of the UFQFPN-48 package on the STM32L431CCU6, and is it suitable for low-volume hand soldering?
The UFQFPN-48 is an ultra-thin QFN package measuring 7 mm × 7 mm with an exposed thermal pad underneath. All pins of the STM32L431CCU6 are hidden beneath the package, so reflow soldering or a hot-air station is required—manual soldering with a conventional iron is not feasible. This package greatly saves PCB area but demands precise stencil design and controlled reflow profiles, making the STM32L431CCU6 best suited for automated SMT production. For prototyping, use a QFN adapter board or the compatible NUCLEO development board for initial validation.
4. What applications is STM32L431CCU6 suitable for?
With its compact 48-pin package, 256 KB Flash, USB connectivity, and excellent power efficiency, the STM32L431CCU6 is ideal for battery-powered devices with moderate code size and stringent space/power requirements, such as portable medical monitors, wireless sensor nodes, miniature USB dongles, consumer wearables, and ultra-compact IoT endpoints requiring simple USB connectivity.
5. How does STM32L431CCU6 differ from STM32L432KCU6?
They differ in package and I/O count: the STM32L431CCU6 is a 48-pin QFN with 38 I/Os, while KCU6 is a 32-pin QFN with 26 I/Os. The STM32L431CCU6 provides 256 KB Flash and USB OTG FS but lacks CAN 2.0B and SAI audio interface. The L432KCU6 has fewer I/Os but adds an SAI audio interface. If your project does not require digital audio and benefits from more I/Os and larger Flash, the STM32L431CCU6 is the better choice.
6. What's the difference between STM32L431CCU6 and STM32L431RCT6?
Both share identical core, memory (256 KB Flash, 64 KB SRAM), and peripherals (USB OTG FS, no CAN/SAI). The only differences are the package and I/O count: the STM32L431CCU6 uses a 48-pin QFN (38 I/Os), while RCT6 uses a 64-pin LQFP (52 I/Os). The STM32L431CCU6 is better for extremely space-constrained designs, whereas RCT6 offers easier hand-soldering and more I/O expansion.
7. What if my project needs CAN or SAI? Can STM32L431CCU6 handle that?
The STM32L431CCU6 does not include native CAN or SAI controllers. If these interfaces are essential, consider the STM32L432 (with SAI) or STM32L433 (with both CAN and SAI). If you must use the STM32L431CCU6, you could add an external CAN controller (e.g., MCP2515) via SPI or an external audio codec via I2S/SPI, but this will increase circuit complexity—so evaluate carefully during component selection.
8. Is 64 KB SRAM on the STM32L431CCU6 enough when running a USB stack, and how can memory be optimized?
The 64 KB SRAM on the STM32L431CCU6 can comfortably run a lightweight RTOS (e.g., FreeRTOS) and standard USB device libraries (CDC, HID). Optimization tips include carefully sizing task stacks, preferring static memory allocation, and leveraging DMA for data transfers to reduce CPU and RAM usage. For applications requiring larger data buffers, external PSRAM or SPI Flash can be added via the Quad SPI interface.
9. Which pins does USB occupy on the STM32L431CCU6 in the 48-pin QFN package, and does it limit GPIO availability?
USB OTG FS on the STM32L431CCU6 requires D+ (PA12) and D- (PA11) as differential data lines, plus typically VBUS detect (PA9) and ID (PA10), consuming a total of four I/Os. With 38 available I/Os, approximately 34 GPIOs remain for other peripherals after USB is configured—providing ample flexibility. Use STM32CubeMX for pin planning to avoid conflicts.
10. What is the power consumption like on the STM32L431CCU6?
The STM32L431CCU6 inherits the STM32L4 series' renowned ultra-low-power performance: Shutdown mode draws only ~33 nA, Standby mode ~125 nA, Stop 2 mode ~1.2 µA (~1.4 µA with RTC), and Run mode ~100 µA/MHz (LDO mode). With multiple low-power modes and fast wake-up, the STM32L431CCU6 is perfectly suited for battery-powered devices demanding long battery life.