STM8S003
Brand: ST
STM8S003 is a 8-bit STM8 microcontroller from STMicroelectronics, designed for BLHeli_S drone ESCs, battery management systems, and cost-sensitive embedded control. Superb Automation supplies genuine STM8S003 with full traceability, competitive pricing, and fast global delivery — supporting prototype to production volumes for drone, robotics, and industrial customers worldwide.
Product Specifications
STM8S003 — 8-Bit STM8 Value Line MCU Series for Drone ESCs, BMS, and Sensor Nodes
The STM8S003 is STMicroelectronics' Value Line 8-bit MCU series based on the proprietary STM8 core at 16 MHz, offering 8 KB Flash and 1 KB SRAM. Available in TSSOP-20 (STM8S003F3), LQFP-32 (STM8S003K3), UFQFPN-20, and SO-20 packages, this family is the most cost-effective and widely deployed MCU for BLHeli_S drone ESCs — powering millions of brushless motor controllers worldwide. The STM8S003 base part number covers the complete Value Line subfamily, providing a range of pin counts and packages for ESC, BMS monitoring, PDB control, and LED driver applications.
Part Number Decoded — Field by Field
| Field | Value | Meaning |
|---|---|---|
| STM8 | Product Family | STMicroelectronics 8-bit MCU — STM8 proprietary core |
| S | Product Type | Standard — mainstream general-purpose series (2.95–5.5V) |
| 003 | Sub-Family | Value Line — cost-optimized, entry-level 8-bit MCU family |
| — | Package Variants | F3 = TSSOP-20, K3 = LQFP-32, P3 = TSSOP-20, F3P6 = TSSOP-20 industrial, K3T6 = LQFP-32 industrial |
Quick Specifications
| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Part Number Base | STM8S003 (covers all package/pin variants) |
| Core | STM8 (8-bit proprietary, Harvard architecture) |
| Max Clock | 16 MHz (internal 128 kHz / 16 MHz HSI RC or external crystal) |
| Flash | 8 KB (with read-while-write; 10K erase/write cycles) |
| SRAM | 1 KB |
| EEPROM | 128 bytes (true data EEPROM, 300K write cycles) |
| Supply Voltage | 2.95V – 5.5V |
| Operating Temperature | −40°C to +85°C (industrial), −40°C to +105°C (optional) |
| Package Options | TSSOP-20, LQFP-32, UFQFPN-20, SO-20 |
| GPIO Range | 16 (TSSOP-20) to 28 (LQFP-32) |
| ADC | 1× 10-bit, 4–5 channels (package-dependent) |
| Timers | 3× 16-bit: 1× advanced (complementary PWM + dead-time), 2× general-purpose |
| Communication | 1× UART, 1× SPI, 1× I²C |
| Debug | SWIM (Single Wire Interface Module) |
Product Overview
The STM8S003 series represents ST's answer to the question: "What is the absolute minimum-cost MCU that can still run BLHeli_S?" The answer has become industry-defining. The STM8S003 Value Line delivers genuine 16 MHz 8-bit processing, a hardware advanced PWM timer with dead-time insertion, a 10-bit ADC for phase current and voltage sensing, and UART/SPI/I²C communication — at a price point that enables BLHeli_S ESCs to retail for under $5. No other MCU family offers this combination of hardware features, software ecosystem maturity (BLHeli_S), and cost structure.
In the drone ecosystem, the STM8S003 is more than an MCU — it is the standardized platform around which the entire BLHeli_S ecosystem was built. The firmware, configuration tools (BLHeliSuite), DShot/Oneshot/Multishot protocol stacks, and community knowledge base all assume an STM8S003 at the core. This network effect means drone manufacturers choosing the STM8S003 benefit from millions of flight-hours of firmware validation, an active developer community, and multiple competing PCB reference designs.
Key Features & Benefits
Proven BLHeli_S Ecosystem — Zero Firmware Development
The STM8S003 is the reference platform for BLHeli_S — the dominant open-source ESC firmware for FPV drones. No firmware development is needed: simply flash the pre-compiled BLHeli_S HEX file, configure via BLHeliSuite, and the ESC is ready to fly. All DShot, Multishot, Oneshot, and standard PWM protocols are supported out-of-the-box.
Package Flexibility — TSSOP-20 for Cost, LQFP-32 for I/O
Choose TSSOP-20 (STM8S003F3) for the most compact and cost-effective ESC design (6.5×4.4 mm, 0.65 mm pitch) or LQFP-32 (STM8S003K3) when additional GPIO is needed for onboard current sensing, voltage monitoring, and LED control. The UFQFPN-20 option provides an even smaller footprint for ultra-compact micro-drone ESCs.
Advanced PWM Timer — MOSFET-Friendly Gate Drive
The 16-bit advanced-control timer generates complementary PWM outputs with programmable dead-time insertion (0–128 µs in 8 ns steps) — the critical feature that prevents cross-conduction (shoot-through) in N-channel MOSFET half-bridges. This timer also supports center-aligned PWM for reduced EMI and smoother motor current waveforms.
Industrial Temperature Range — Outdoor Drone Ready
The -6 temperature suffix guarantees operation from −40°C to +85°C — essential for FPV drones flying in winter conditions, high-altitude platforms, and agricultural UAVs exposed to full sun. The 2.95–5.5V supply range tolerates the voltage fluctuations common in LiPo-powered systems.
Target Applications
BLHeli_S / Bluejay ESC Motor Controllers
The primary and most iconic application. Powers individual ESCs (20A–60A), 4-in-1 AIO ESCs, and whoop-sized 5A controllers. Runs BLHeli_S and Bluejay (open-source BLHeli_S fork with bidirectional DShot, variable PWM frequency, and 48–96 kHz support) firmware for smooth, quiet motor operation.
Battery Management System (BMS) Monitor Nodes
The STM8S003 ADC scans cell voltages while the I²C/UART interface communicates pack health data to the flight controller. The 128-byte EEPROM stores cycle counts and calibration data. Suitable for 1S–4S smart-battery packs.
PDB Current Sensor and LED Controller
Combines current sensing (shunt amplifier + ADC), voltage monitoring, and WS2812B LED strip control on a single chip — all powered directly from the LiPo battery through a simple LDO.
Frequently Asked Questions
Which STM8S003 package should I choose for a BLHeli_S ESC?
For individual ESCs (20×12 mm PCB): TSSOP-20 (STM8S003F3P6) — smallest, cheapest, adequate pins. For 4-in-1 AIO ESCs or ESCs with onboard current sensing and LEDs: LQFP-32 (STM8S003K3T6C) — more GPIO for additional features. For micro whoop ESCs: UFQFPN-20 — smallest footprint but requires precision SMT placement.
Is the STM8S003 still in active production?
Yes. Despite being introduced over a decade ago, ST continues active production of the STM8S003 series with no announced discontinuation. The STM8 platform is maintained in ST's longevity program (10-year commitment from introduction). With hundreds of millions of units deployed, it is one of ST's highest-volume 8-bit products and is expected to remain available for the foreseeable future.
What development tools do I need for STM8S003?
Minimal toolchain: ST-LINK/V2 debugger (~$20) for SWIM programming and debugging, STVD (free IDE with COSMIC C compiler), and STVP (free programmer). For BLHeli_S specifically, only BLHeliSuite (free Windows tool) is needed to flash pre-compiled firmware via a USB linker or Arduino-based 4-way interface.
Ordering Information
| Orderable Part Number | Package | Packaging | Temperature |
|---|---|---|---|
| STM8S003F3P6 | TSSOP-20 | Tube | −40°C to +85°C |
| STM8S003F3P6TR | TSSOP-20 | Tape & Reel | −40°C to +85°C |
| STM8S003K3T6C | LQFP-32 | Tray | −40°C to +85°C |
| STM8S003F3U6TR | UFQFPN-20 | Tape & Reel | −40°C to +85°C |
Design Resources
- Datasheet (DS7147): STM8S003F3 / STM8S003K3 — Complete datasheet covering all STM8S003 package variants with electrical, timing, and mechanical specifications.
- Reference Manual (RM0016): STM8S and STM8AF Series — Comprehensive register-level documentation for the STM8S product family.
- BLHeli_S GitHub:
bitdump/BLHeli— Reference open-source ESC firmware. Contains assembly source, HEX binaries, and BLHeliSuite configuration tool. - Bluejay GitHub:
mathiasvr/bluejay— Modern open-source BLHeli_S fork with bidirectional DShot, variable PWM (24–96 kHz), and improved startup performance. - STVD + COSMIC: Free IDE and C compiler toolchain — the standard development environment for STM8 firmware development.
- Application Note AN3258: Getting Started with STM8S — Step-by-step tutorial for first-time STM8 development.
Request a Quote
SUPERB Automation supplies genuine STMicroelectronics STM8S003 series MCUs with full traceability and batch-level QA documentation. The STM8S003 Value Line is the definitive 8-bit MCU for BLHeli_S drone ESCs — with proven field reliability, mature firmware ecosystem, and the industry's lowest cost-per-ESC. Whether you need prototype quantities for ESC firmware development or production volumes for drone BMS and PDB controller manufacturing, 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.