STMicroelectronics STM32F103C6U6A

Overview

STM32F103C6U6A from STMicroelectronics is a low-density performance-line ARM Cortex-M3 microcontroller featuring 32 KB Flash, 10 KB SRAM, 72 MHz CPU clock, USB 2.0 full-speed interface, and CAN 2.0B controller-used in industrial motor control, sensor node firmware, and embedded HMI subsystems.

For engineers reviewing the STM32F103C6U6A datasheet, STM32F103C6U6A pinout, STM32F103C6U6A application, or STM32F103C6U6A equivalent, key selection criteria include Flash/SRAM size, USB/CAN co-integration, 48-pin UFQFPN package constraints, and real-time peripheral count (6 timers, 2×12-bit ADCs, 6 communication interfaces).

Technical Context

The STM32F103C6U6A implements an ARM Cortex-M3 core with Harvard architecture, single-cycle multiplication, hardware divide, and nested vectored interrupt controller (NVIC) supporting up to 60 interrupts. It integrates a 72 MHz PLL fed by 4–16 MHz external crystal or internal 8 MHz RC oscillator.

Its peripheral set includes two 12-bit, 1 µs ADCs with temperature sensor input, seven-channel DMA supporting concurrent transfers across USART, SPI, I²C, timers, and ADC, plus dual watchdogs (independent + window) and SysTick for deterministic timing.

Key Specifications

Pinout & Package

STM32F103C6U6A uses the UFQFPN48 package: 48-pin ultra-thin fine-pitch quad flat no-lead with exposed thermal pad (EP), compliant with ECOPACK® environmental standards.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STM32F103C8T6, the C6U6A trades memory headroom for smaller footprint and lower cost in space-constrained USB/CAN edge nodes; versus LPC1769, it offers tighter integration of USB/CAN in a lower-power, lower-BOM solution where Ethernet is unnecessary.

Availability

STM32F103C6U6A is available at Aetrix Electronics and suitable for industrial motor control, USB-CAN bridge devices, and smart sensor nodes requiring stable component supply across multi-year production cycles.

Supply support for STM32F103C6U6A 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, specializing in microcontrollers, power management, and automotive-grade ICs with strong industrial and consumer market presence.

The STM32F103x6 series targets cost-sensitive, performance-oriented embedded applications demanding USB connectivity, real-time control, and industrial bus interfaces - designed specifically for compact, low-power edge nodes and motor drive subsystems.

FAQ

What is the maximum operating frequency and how is it achieved?

The STM32F103C6U6A achieves 72 MHz CPU clock via its internal PLL, which multiplies the input from either a 4–16 MHz external crystal oscillator or the internal 8 MHz RC oscillator. The PLL requires proper configuration of prescalers and multipliers in the RCC registers, and stable clock startup sequences must be followed per the reference manual to avoid lock failure or system reset.

Does this MCU support USB device functionality without external components?

Yes - the STM32F103C6U6A integrates a full-speed USB 2.0 device controller with internal transceiver. Only a 1.5 kΩ pull-up resistor on the DP line is required for enumeration; no external PHY or level shifters are needed. The USB stack runs entirely in firmware using ST's HAL or LL libraries, supporting CDC, HID, and MSC classes.

How many ADC channels are accessible in the UFQFPN48 package?

In the UFQFPN48 package, 10 ADC channels are physically available: ADC1_IN0–IN9 mapped to PA0–PA7, PB0–PB1. Channels beyond IN9 (e.g., temperature sensor, VREFINT) are internal and do not require pins. All 10 channels support 12-bit resolution and 1 µs conversion time with programmable sampling periods.

Is the CAN interface fully implemented in hardware, including filtering and message RAM?

Yes - the bxCAN peripheral provides full CAN 2.0B Active compliance, including hardware acceptance filtering (14 32-bit or 28 16-bit filters), 14-message transmit/receive FIFOs, automatic retransmission, and bus-off recovery. No external CAN controller is required; only a physical-layer transceiver (e.g., TJA1050) connects PB8/PB9 to the CAN bus.