STM32F051K6U6 ST Mainstream Arm Cortex-M0 Access Line 32-bit MCU 32KB Flash 48MHz CPU 12-bit ADC DAC UFQFPN-32

STM32F051K6U6 Product Overview

The STM32F051K6U6 is a mainstream Arm Cortex-M0 access line MCU from STMicroelectronics, UFQFPN-32 package (5×5×0.55 mm). 48 MHz Cortex-M0 core, 32 KB Flash, 8 KB SRAM. Integrates 12-bit ADC (up to 13 channels, 1.0 μs), 12-bit DAC, 2 analog comparators, HDMI CEC, 5-channel DMA, up to 18-channel capacitive touch, calendar RTC (V_BAT backup), up to 11 timers (1×16-bit 7-channel advanced-control/6-ch PWM/deadtime/emergency stop, 1×32-bit GP/IC/OC/IR decode, 5×16-bit GP incl. 1 basic timer for DAC, independent/window WDG, SysTick), 1×I2C (1 Mbit/s Fast Mode Plus, 20 mA sink), 1×SPI (18 Mbit/s, I2S mux), 2×USART (1×ISO7816/LIN/IrDA/auto baud/wakeup). 27 I/Os. VDD 2.0 V–3.6 V, VDDA 2.4 V–3.6 V, -40 °C to 85 °C, ECOPACK®2.

STM32F051K6U6 Core Features

Core: Arm Cortex-M0 48 MHz, NVIC Memory: 32 KB Flash, 8 KB SRAM (HW parity), CRC 12-bit ADC: Up to 13 channels, 1.0 μs, 0–3.6 V, analog supply 2.4 V–3.6 V 12-bit DAC: 1 channel, buffered output 2 Analog Comparators: Programmable input/output HDMI CEC: Wakeup on header 18-ch Capacitive Touch: Keys/linear/rotary 5-ch DMA: Flexible mapping 11 Timers: 1×16-bit 7-ch advanced-control (6-ch PWM/deadtime/emergency stop), 1×32-bit GP (4 IC/OC/IR decode), 5×16-bit GP (incl. 1 basic timer for DAC), independent/window WDG, SysTick Communication: 1×I2C (1 Mbit/s Fast Mode Plus, SMBus/PMBus, 20 mA sink, Stop wakeup), 1×SPI (18 Mbit/s, 4–16 bit frame, I2S mux), 2×USART (master sync SPI/modem, 1×ISO7816/LIN/IrDA/auto baud/wakeup) Low Power: Sleep/Stop/Standby Clock: 4–32 MHz XTAL, 32 kHz RTC XTAL (calibrated), 8 MHz RC (×6 PLL), 40 kHz RC I/Os: 27 fast I/Os, all ext. interrupt mappable Reliability: POR/PDR, PVD, SWD, 96-bit unique ID Supply/Temp: VDD 2.0 V–3.6 V, VDDA 2.4 V–3.6 V, -40 °C to 85 °C Package: UFQFPN-32 (5×5×0.55 mm), Tray

STM32F051K6U6 Applications

Consumer: Remote controls, toothbrushes, toys, handhelds, PC peripherals Industrial: PLCs, sensor transmitters, RS-485 nodes, actuators Motor Control: Fans, pumps, small motors (6-ch PWM/deadtime/emergency stop) Automotive: Light/window control, sensor nodes Home Appliances: Panels, HVAC, alarms, smart lighting IoT: Wireless sensors, environmental monitoring, smart home LED Lighting: Dimming, RGB strips, SMPS HMI: Touch keys/sliders/wheels

STM32F051K6U6 Key Advantages

UFQFPN-32 Ultra-Compact: 5×5 mm, 27 I/Os, ideal for space-constrained designs 32 KB Flash + 8 KB SRAM: Balanced configuration in the STM32F0 access line for medium-complexity applications 12-bit ADC + DAC + Dual Comparators: Complete analog signal chain without external analog ICs 12-bit DAC: Buffered output, rare in this class, supports audio/sensor excitation/control loops 18-ch Capacitive Touch: No external touch IC needed, reduces BOM HDMI CEC: For digital TV, A/V receivers, and consumer electronics 5-ch DMA: Direct peripheral-to-memory transfers, offloads CPU I2C Fast Mode Plus: 1 Mbit/s, 20 mA sink, SMBus/PMBus 11 Timers: Advanced-control/PWM/deadtime/emergency stop + 32-bit IR decode + 5 GP Calendar RTC: Alarm/periodic wakeup, V_BAT backup Mature STM32 Ecosystem: CubeIDE/CubeMX/HAL/development boards Cost-Effective: 32-bit ARM + ADC + DAC + capacitive touch, ideal upgrade from 8/16-bit MCUs

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 the STM32F051K6U6 and what makes it unique in a 32‑pin Cortex‑M0?
   The STM32F051K6U6 is a 48 MHz Arm Cortex‑M0 microcontroller with 32 KB Flash and 8 KB SRAM, housed in a tiny UFQFPN‑32 package. It stands out by integrating a 12‑bit DAC and an HDMI CEC controller—peripherals that are rarely found together in such a compact, low‑cost device. Combined with a 12‑bit ADC, multiple timers, and standard serial interfaces (USART, SPI, I2C), it is an ideal single‑chip solution for space‑constrained industrial sensors, portable medical devices, and HDMI‑connected consumer electronics that need both analog output and digital control without paying for unused memory.

2. How does the STM32F051K6U6 differ from the STM32F051K8U6? When should I choose the K6U6?
   Both share the same core, 8 KB SRAM, DAC, HDMI CEC, and all other peripherals in the identical UFQFPN‑32 package. The only difference is Flash size: the K6U6 provides 32 KB, while the K8U6 offers 64 KB. Choose the K6U6 when your firmware fits comfortably within 32 KB and you want the absolute lowest cost. The pin‑compatible K8U6 is a direct drop‑in upgrade if you later need double the Flash with zero PCB changes.

3. How does the STM32F051K6U6 compare to the popular STM32F103C8T6? What are the main trade‑offs?
   The STM32F103C8T6 is a 72 MHz Cortex‑M3 with 64 KB Flash, 20 KB SRAM, USB, and CAN in an LQFP‑48 package. The STM32F051K6U6 runs at a lower 48 MHz and uses a simpler Cortex‑M0 core, has less SRAM (8 KB vs 20 KB), and removes USB and CAN. However, it adds a built‑in 12‑bit DAC and an HDMI CEC controller, comes in a much smaller 32‑pin package, and consumes significantly less power. Choose the F051K6U6 when you need a very compact design, analog voltage output, or HDMI connectivity, and you do not require USB, CAN, or the larger SRAM and CPU speed of the F103.

4. Is 32 KB Flash and 8 KB SRAM really enough for a real‑time control application? What can I fit in this space?
   Absolutely, for focused and well‑optimized tasks. 32 KB of Flash can comfortably hold a USART/SPI/I2C communication stack, sensor drivers, a simple control loop, and application logic. The 8 KB SRAM requires disciplined buffer management—using DMA for serial transfers and keeping large arrays in Flash—but is sufficient for task stacks and small data buffers. Many proven designs such as HDMI‑CEC controllers, smart sensors, and home appliance control panels run within this memory envelope. If your code later outgrows the 32 KB limit, the pin‑compatible STM32F051K8U6 (64 KB Flash) provides a direct upgrade path with no hardware changes.

5. Does the STM32F051K6U6 really have a DAC and HDMI CEC? Why are these features important in such a small package?
   Yes, the STM32F051K6U6 integrates a 2‑channel 12‑bit DAC and a dedicated HDMI CEC controller. The DAC allows you to generate analog voltage outputs for sensor excitation, waveform generation, or audio playback without an external DAC chip. The HDMI CEC controller handles the low‑level protocol for consumer electronics control, enabling the MCU to communicate with TVs, projectors, and set‑top boxes over the HDMI cable. These two peripherals make the F051K6U6 a rare, highly capable device in the ultra‑compact 32‑pin category, perfect for mixed‑signal and AV‑connected applications.

6. What low‑power modes does the STM32F051K6U6 support, and can it run from a coin‑cell battery?
   The chip supports Sleep, Stop, and Standby modes. In Stop mode with the main regulator off and all 8 KB SRAM retained, the typical current is around 3 µA—extremely low for a 32‑bit MCU. Wake‑up from Stop is fast enough to respond to external interrupts or communication events. The 48 MHz Cortex‑M0 core is inherently power‑efficient, making the F051K6U6 an excellent choice for battery‑powered sensors, energy‑harvesting devices, and portable instruments that spend most of their time in deep sleep and wake periodically to acquire and transmit data.

7. How many I/O pins does the UFQFPN‑32 package provide, and what peripherals can I use simultaneously?
   The UFQFPN‑32 package offers up to 25 general‑purpose I/O pins. With careful planning, you can allocate one USART, one SPI, one I2C, the HDMI CEC line, the two DAC outputs, and still have a few pins left for ADC input or GPIO. The flexible pin‑multiplexing of the STM32F0 series helps you maximize the use of every pin. STM32CubeMX is essential for verifying the exact pin‑out and ensuring no conflicts in such a tightly constrained package.

8. Can I perform over‑the‑air (OTA) firmware updates with the 32 KB single‑bank Flash?
   Yes, but only with extreme code‑size discipline. A minimal bootloader (2–4 KB) and a very compact application must be implemented. The 8 KB SRAM can buffer very small firmware chunks received via USART, SPI, or an external wireless module, and the update is performed sector‑by‑sector. An A/B update scheme is impossible; a verified download‑and‑overwrite approach is the only practical method. For designs that require comfortable OTA headroom, consider the pin‑compatible STM32F051K8U6 (64 KB Flash) or STM32F091CCT6 (256 KB Flash) in a larger package.

9. How does the STM32F051K6U6 compare to the STM32F030K6T6? Is it worth the upgrade?
   The STM32F030K6T6 is a 48 MHz Cortex‑M0 with 32 KB Flash and 4 KB SRAM in an LQFP‑32 package. The STM32F051K6U6 doubles the SRAM (8 KB), adds a 12‑bit DAC and an HDMI CEC controller, and provides more advanced timers and richer communication peripherals. For a small additional cost, the F051K6U6 offers significantly more memory headroom and valuable analog/output features, making it a strong upgrade for F030 designs that have outgrown their SRAM limits or need DAC/CEC functionality.

10. What are the most typical applications for the STM32F051K6U6?
    It is widely used in compact HDMI‑CEC interface modules, smart sensors with analog output, portable medical devices, power tools, LED lighting controllers, and cost‑sensitive industrial nodes. Any space‑constrained embedded system that needs a proven 32‑bit core with a built‑in DAC, HDMI connectivity, and a tiny 32‑pin footprint at the absolute lowest cost is a strong fit for the F051K6U6.