STM32F103RCT6
Brand: ST
The STM32F103RCT6 belongs to ST's STM32F1 Performance Line — the series that defined the ARM Cortex-M3 ecosystem in the maker, hobbyist, and professional drone communities. Its combination of 72 MHz processing, extensive communication peripherals, hardware PWM for motor control, and industrial temperature range makes it the natural choice for flight controllers spanning micro whoops to professional mapping UAVs.
With 256 KB Flash and 48 KB SRAM, the STM32F103RCT6 is a sweet spot for ArduPilot fixed-wing platforms and feature-rich iNav builds. The LQFP-64 package unlocks 51 GPIO, the 12-channel DMA offloads IMU/barometer/GPS sensor fusion from the CPU, and dual advanced timers enable up to 12 hardware PWM channels — enough for octocopter configurations with servo-driven gimbals.
Product Specifications
STM32F103RCT6 — ARM Cortex-M3 MCU for Drone Flight Controllers by STMicroelectronics
The STM32F103RCT6 is STMicroelectronics' high-density performance line 32-bit ARM Cortex-M3 microcontroller, running at 72 MHz with 256 KB Flash and 48 KB SRAM. Packaged in a LQFP-64, it serves as the flight controller brain for open-source drone firmware — Betaflight, Cleanflight, iNav, and ArduPilot — across board designs from micro AIO whoops to full-size professional mapping UAVs. With 2× 12-bit (16 channels), 12-channel, and a comprehensive set of communication interfaces (USART, SPI, I²C, CAN, USB), it delivers a complete sensor-fusion and motor-control pipeline for the global drone ecosystem.
Part Number Decoded — Field by Field
| Field | Value | Meaning |
|---|---|---|
| STM32 | Product Family | STMicroelectronics 32-bit ARM-based MCU |
| F | Core Type | Foundation — general-purpose mainstream series (ARM Cortex-M3) |
| 103 | Sub-Family | Performance Line — 72 MHz, motor control capable, USB & CAN available |
| R | Pin Count | 64 pins (LQFP-64) |
| C | Flash Size | 256 KB |
| T | Package | LQFP (Low-profile Quad Flat Package) |
| 6 | Temperature Range | −40°C to +85°C (industrial) |
Quick Specifications
| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Part Number | STM32F103RCT6 |
| Core | ARM Cortex-M3 |
| Max Clock | 72 MHz |
| Flash | 256 KB |
| SRAM | 48 KB |
| Package | LQFP-64 |
| Supply Voltage | 2.0V – 3.6V |
| Operating Temperature | −40°C to +85°C |
| GPIO | 51 |
| ADC | 2× 12-bit (16 channels) |
| Timers | 4× 16-bit GP, 2× 16-bit advanced (PWM), 2× 16-bit basic, 2× watchdog, 1× SysTick |
| Communication | 3× USART + 2× UART, 3× SPI (2× SPI + 1× SPI/I²S), 2× I²C, 1× CAN 2.0B, 1× USB 2.0 Full Speed |
| DMA | 12-channel |
| Debug | SWD + JTAG |
Product Overview
The STM32F103RCT6 belongs to ST's STM32F1 Performance Line — the series that defined the ARM Cortex-M3 ecosystem in the maker, hobbyist, and professional drone communities. Its combination of 72 MHz processing, extensive communication peripherals, hardware PWM for motor control, and industrial temperature range makes it the natural choice for flight controllers spanning micro whoops to professional mapping UAVs.
With 256 KB Flash and 48 KB SRAM, the STM32F103RCT6 is a sweet spot for ArduPilot fixed-wing platforms and feature-rich iNav builds. The LQFP-64 package unlocks 51 GPIO, the 12-channel DMA offloads IMU/barometer/GPS sensor fusion from the CPU, and dual advanced timers enable up to 12 hardware PWM channels — enough for octocopter configurations with servo-driven gimbals.
Key Features & Benefits
72 MHz ARM Cortex-M3 — 64-Pin Flight Controller Powerhouse
At 72 MHz with single-cycle multiply and hardware divide, the Cortex-M3 core delivers deterministic real-time control for drone flight stabilization. It sustains a 4 kHz gyroscope update rate with PID loops running on 4–6 motor axes — the practical performance ceiling for SPI-gyro-based flight controllers in the F103 class, without overclocking or migrating to F4 silicon.
256 KB Flash + 48 KB SRAM — The iNav / ArduPilot Sweet Spot
256 KB Flash provides ample room for iNav (navigation-enabled) and lightweight ArduPilot builds. The 48 KB SRAM comfortably runs the Extended Kalman Filter, waypoint navigation, and MAVLink telemetry stacks — with margin for custom flight modes and logging.
Industrial Temperature −40°C to +85°C — Outdoor-Ready
The temperature suffix guarantees operation from −40°C to +85°C — essential for drones flying in cold high-altitude environments, agricultural UAVs operating in extreme heat, and industrial inspection platforms where reliability across thermal cycles is non-negotiable.
12-channel — Offloads Sensor Fusion and Serial I/O
The 12-channel DMA controller offloads SPI gyro/accelerometer reads, USART telemetry streaming (CRSF, SmartPort, MSP, MAVLink), I²C barometer/magnetometer polling, and ADC current-sense sampling from the CPU — freeing core cycles for the PID control loop and enabling lower-latency flight characteristics even under heavy sensor loads.
Dual Advanced Timers — Up to 12 Hardware PWM Channels
Two 16-bit advanced-control timers with complementary outputs and dead-time insertion drive up to 12 independent PWM channels — directly supporting octocopter (8 motors) or hexacopter (6 motors + 2 servo gimbals) configurations using protocols from standard PWM through Oneshot125, Multishot, and DShot. Four general-purpose timers handle input capture for PPM/ SBUS receivers.
USB 2.0 Full Speed + CAN 2.0B — One Cable for Config, One Bus for Expansion
The on-chip USB 2.0 Full Speed peripheral eliminates external USB-UART ICs (e.g., CP2102, CH340G), reducing BOM cost and board complexity. The CAN 2.0B interface enables integration with UAVCAN/DroneCAN peripherals (GPS modules, airspeed sensors, ESC telemetry nodes) for modular, future-proof drone architectures.
Target Applications
Entry-Level & Mid-Range Drone Flight Controllers
The STM32F103RCT6 is a staple of open-source drone FCs in the 64-pin form factor — powering boards like the Omnibus F3, Matek F405 (F1-era), and SP Racing F3 derivatives. With 256 KB Flash and 48 KB SRAM, it runs Betaflight, Cleanflight, iNav, and lightweight ArduPilot builds with enough I/O for GPS, compass, barometer, OSD, and serial RX all connected simultaneously.
ArduPilot Lightweight & Mid-Range Platforms
With 256 KB Flash and 48 KB SRAM, the STM32F103RCT6 comfortably hosts ArduPilot (ChibiOS) builds with GPS navigation, waypoint missions, and telemetry — suitable for fixed-wing FPV platforms, autonomous mapping drones, and university rover/copter competitions where the Cortex-M3's deterministic real-time performance is preferred over raw clock speed.
Sensor Hub & Companion Processor
As a dedicated sensor-fusion node, the STM32F103RCT6 offloads IMU (MPU6000/ICM-20602), barometer (BMP280/MS5611), magnetometer (QMC5883L), and GPS (UBlox NEO-M8) processing from a host application processor (Raspberry Pi, Jetson Nano, or STM32H7). It streams pre-filtered attitude quaternions and altitude data via USART or SPI at configurable rates up to 1 kHz.
Distributed Robotics Motor Controllers
The advanced PWM timer (with complementary outputs and dead-time insertion) plus CAN 2.0B interface make the STM32F103RCT6 an excellent choice for distributed motor-control nodes in ground robots, robotic arms, AGVs, and multi-axis gimbals. The 12-channel handles encoder quadrature decoding and current-sense ADC reads without CPU intervention.
Industrial Sensor & Actuator Nodes
In industrial environments, the STM32F103RCT6 serves as a low-cost Modbus RTU (RS-485) or CANopen slave node, bridging analog sensors (4–20 mA, 0–10V) and digital actuators to PLCs and SCADA systems. The −40°C to +85°C temperature range and 2.0V–3.6V supply suit unregulated industrial power rails.
F103 Series Variant Comparison
| Feature | STM32F103RCT6 | STM32F103VCT6 | STM32F103VET6 | STM32F103CBT6 |
|---|---|---|---|---|
| Package | LQFP-64 | LQFP-100 | LQFP-100 | LQFP-48 |
| Flash | 256 KB | 256 KB | 512 KB | 128 KB |
| SRAM | 48 KB | 48 KB | 64 KB | 20 KB |
| GPIO | 51 | 80 | 80 | 37 |
| USART | 3 | 5 | 5 | 3 |
| SPI | 3 | 3 | 3 | 2 |
| FPU | No (Cortex-M3 — no hardware FPU) | |||
| Best For | ArduPilot fixed-wing, iNav, Betaflight | Complex drone & industrial, iNav | Complex drone & industrial, iNav | Betaflight, more Flash headroom |
STM32F103 vs Competing Entry-Level Flight Controller MCUs
| Feature | STM32F103RCT6 (ST) | GD32F103C8T6 (GigaDevice) | AT32F403AC8T6 (Artery) | APM32F103C8T6 (Geehy) |
|---|---|---|---|---|
| Core | ARM Cortex-M3 @ 72 MHz | ARM Cortex-M3 @ 108 MHz | ARM Cortex-M4F @ 240 MHz | ARM Cortex-M3 @ 96 MHz |
| Flash / SRAM | 256 KB / 48 KB | 64 KB / 20 KB | 64 KB / 96 KB | 64 KB / 20 KB |
| Package | LQFP-64 | LQFP-48 | LQFP-48 | LQFP-48 |
| FPU | No | No | Yes (single-precision) | No |
| Betaflight Support | F3 target (up to BF 4.0.x) | Unofficial (F3 port) | No (M4F arch diff) | No |
| Availability (Q3 2026) | Stable, 8–12 week lead | Good (domestic China) | Good | Good |
Frequently Asked Questions
How does the STM32F103xC compare to the STM32F103x8 (64 KB) series?
The STM32F103RCT6 belongs to the high-density F103 line with 256 KB Flash and 48 KB SRAM — more than double the 64 KB/20 KB of medium-density parts. It also gains a 12-channel DMA (vs. 7), additional USARTs, an extra SPI/I²S, and a second advanced timer. For ArduPilot and feature-rich iNav builds, this is the minimum recommended density.
How do I flash firmware to the STM32F103RCT6?
Flash via Betaflight Configurator (or STM32CubeProgrammer) over USB DFU: (1) Assert BOOT0 high (connect to 3.3V or press BOOT button if present). (2) Connect USB — the MCU enters the ROM serial bootloader. (3) In Betaflight Configurator select "STM32F103" as target, load the .hex firmware, click "Flash Firmware." After flashing, return BOOT0 to GND and reconnect USB for normal COM-port operation. For production, SWD (ST-Link/V2) is faster and does not require BOOT0 manipulation.
Can the STM32F103RCT6 run Betaflight 4.4+?
No. Betaflight dropped official F3 target support after BF 4.0.x. The STM32F103 (Cortex-M3) is classified as an F3 target. For Betaflight 4.4+, an STM32F405/F411/F722/F745/H743 (F4 or F7 target) is required. The STM32F103RCT6 remains viable for legacy Betaflight 3.x/4.0.x builds and for Cleanflight/iNav F3 targets with feature limitations.
Is the STM32F103RCT6 affected by semiconductor shortages in 2026?
As of mid-2026, STM32F103 supply has normalized significantly versus the 2021–2023 crisis. Lead times are 8–12 weeks, and spot-market availability through Asia-based distributors is good. However, volume pricing remains elevated above pre-shortage levels. SUPERB Automation maintains relationships with multiple authorized and independent channels to secure competitive pricing and consistent delivery.
What is the minimum order quantity (MOQ) for the STM32F103RCT6?
Contact SUPERB Automation for a tailored quote. We support quantities from prototype tray (1–10 pcs) to full production volumes. Send your target quantity and delivery timeline — we provide competitive pricing with full traceability and batch-level QA documentation.
Ordering Information
| Orderable Part Number | Package | Packaging | Temperature |
|---|---|---|---|
| STM32F103RCT6 | LQFP-64 | Tray (160 pcs/tray) | −40°C to +85°C |
| STM32F103RCT6TR | LQFP-64 | Tape & Reel (1,000 pcs/reel) | −40°C to +85°C |
Design Resources
Datasheet: STM32F103xE — Complete datasheet with pin definitions, electrical characteristics (I/O DC/AC parameters, current consumption, timing), and package mechanical drawings.
Reference Manual (RM0008): STM32F1xx advanced ARM-based 32-bit MCUs — Full register-level documentation covering all peripherals (GPIO, timers, ADC, USART, SPI, I²C, CAN, USB, DMA, RCC, PWR).
Betaflight GitHub:
betaflight/betaflight— Open-source flight controller firmware with STM32F103 (F3) target support (up to BF 4.0.x).STM32CubeIDE: Free ST development environment with STM32CubeMX graphical pinout/clock configurator and built-in GCC toolchain.
AN2586 Application Note: Getting started with STM32F10xxx hardware development — hardware design guidelines, PCB layout recommendations, and oscillator/decoupling requirements.
Request a Quote
SUPERB Automation supplies genuine STMicroelectronics STM32F103RCT6 MCUs with full traceability and batch-level QA documentation. Whether you need a single tray for prototype drone FC builds or pallet-level volumes for production, we source through verified channels with competitive lead times. Contact us with your target quantity, delivery date, and any special packaging or marking requirements — we'll respond with a detailed quotation within 24 hours.