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STMicroelectronics STM32F103C6U6A — Microcontrollers & Processors (MCU / MPU / DSP)

ST STM32F103C6U6A ARM Cortex-M3 MCU, 72MHz, 32KB Flash

MPNSTM32F103C6U6A
Active

STMicroelectronics STM32F1 series, ARM Cortex-M3, 32-bit single-core MCU, 72MHz, 32KB (32K x 8) FLASH, 10K x 8 RAM, 37 I/O, CANbus, I²C, IrDA, LINbus, SPI, UART/USART, USB, A/D 10x12b, -40°C ~ 85°C, 2V ~ 3.6V, 48-UFQFN Exposed Pad, Tray.

$5.8500Ref. price · indicative, final on quote
STMicroelectronics STM32F103C6U6A datasheet (PDF)
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Jul 2026

Specifications

STM32F103C6U6A specifications
ParameterValue
SeriesSTM32F1
MountingSurface Mount
Oscillator typeInternal
Program memory typeFLASH
Voltage - supply (Vcc (Vdd))2V ~ 3.6V
Operating temperature-40°C ~ 85°C (TA)
Speed72MHz
PackageTray
RAM size10K x 8
Core size32-Bit Single-Core
PeripheralsDMA, Motor Control PWM, PDR, POR, PVD, PWM, Temp Sensor, WDT
ConnectivityCANbus, I²C, IrDA, LINbus, SPI, UART/USART, USB
Number of i (O)37
Core processorARM® Cortex®-M3
Case48-UFQFN Exposed Pad
Data convertersA/D 10x12b
Program memory size32KB (32K x 8)

Product details

72 MHz Cortex-M3 in a compact 48-UFQFN — what this MCU covers

The STM32F103C6U6A: The 48-UFQFN package with exposed pad saves board area versus a 48-LQFP, but the pad needs a solid thermal via array under the die to keep junction temperature in check when the I/O bank is fully loaded.

Memory sizing and peripheral set — what fits and what doesn't

With 32 KB of Flash you are looking at a firmware image under about 28 KB after the bootloader and vector table. That rules out full-featured USB stacks with multiple endpoints or a heavy GUI library. The 10 KB SRAM is tight for a TCP/IP stack — a lightweight CANopen or Modbus RTU implementation fits, but you will need to watch the stack and buffer allocation.

It is not AEC-Q100 qualified, so for under-hood automotive you would step up to the STM32F103C8T6 or the automotive-grade STM32F1 derivatives.

STMicroelectronics lists the STM32F103C6U6A as Active. The STM32F1 series is a mature, high-volume platform, so supply through independent distribution is consistent. For dual-sourcing resilience, the pin-compatible STM32F103C8T6 (64 KB Flash, 20 KB SRAM) in 48-LQFP is a drop-in alternative if the board can accommodate the larger package.

Sourcing posture

The active lifecycle means there is no allocation risk from an impending EOL, and the high-volume STM32F1 platform keeps the part in regular production.

Frequently asked questions

What is the closest pin-compatible alternative to STM32F103C6U6A in the STM32F1 family?

The STM32F103C8T6 (64 KB Flash, 20 KB SRAM) in 48-LQFP is a pin-compatible upgrade with double the memory. The STM32F103C6T6 in 48-LQFP shares the same 32 KB Flash but uses a different package — the C6U6A is the UFQFN variant. For a drop-in replacement in the same 48-UFQFN footprint, the STM32F103C8U6 (64 KB Flash) is the direct higher-density sibling.

What is STM32F103C6U6A's maximum core speed?

The ARM Cortex-M3 core runs at 72 MHz maximum. At this clock rate the Flash requires one wait state; the prefetch buffer helps maintain single-cycle execution for sequential code.

How many I/O pins does STM32F103C6U6A have?

The device provides 37 general-purpose I/O pins, mapped across the 48-pin UFQFN package. Most I/O are 5 V tolerant, but the absolute maximum rating per pin should be checked in the datasheet for specific drive conditions.