The STC15 series is a family of 8051-core microcontrollers from STC Micro (宏晶科技) with significant upgrades over the original 8051 design:
- Single-cycle core → 10x faster than classic 8051 🔥
- High-speed internal oscillator (up to 35MHz)
- On-chip EEPROM
- Multiple UARTs (up to 4!)
- Rich peripherals like ADC, PWM, timers, WDT, I2C, SPI
📦 Most Common STC15 Variants Compared
| Feature / Model | STC15F104W | STC15F204EA | STC15W408AS | STC15F2K60S2 | STC15L204EA |
|---|
| Flash | 1 KB | 4 KB | 8 KB | 60 KB | 4 KB |
| RAM | 256 B | 512 B | 512 B | 1 KB | 512 B |
| EEPROM | No | 512 B | 1 KB | 1 KB | 512 B |
| GPIO Pins | 6 | 18 | 26–35 | 35 | 18 |
| ADC Channels (10-bit) | None | 8 | 8 | 8 | 8 |
| PWM Channels | None | 4 | 6 | 6 | 4 |
| UARTs | 1 | 1 | 2 | 4 | 1 |
| Timers | 2 | 4 | 4 | 4 | 4 |
| Speed (MHz) | Up to 30 MHz | Up to 35 MHz | Up to 35 MHz | Up to 35 MHz | Up to 35 MHz |
| Operating Voltage | 3.3–5.5V | 3.3–5.5V | 3.3–5.5V | 3.3–5.5V | 1.8–5.5V ✅ |
| Package Types | SOP8 | SOP20/DIP20 | SOP16/20/28 | LQFP44/DIP40 | SOP20 |
📌 Summary of Key Models
⚡ STC15F104W — Minimalist MCU
- 💡 Great for ultra-simple applications (e.g., blinkers, switch logic)
- No ADC, no EEPROM
- 6 I/O pins max
🧩 STC15F204EA — Entry-level all-rounder
- 8 ADC channels
- Basic PWM and 512B EEPROM
- Compact and cost-effective
🚀 STC15W408AS — Mid-range beast
- Fast, with 8KB Flash and dual UARTs
- Great for serial communication, motor control, and analog sensors
- Fully featured with PWM, ADC, EEPROM, etc.
🧠 STC15F2K60S2 — Powerhouse MCU
- 60 KB Flash and 4 UARTs 🤯
- Excellent for communication-heavy or multitasking applications
- Ideal for larger projects, modbus devices, or sensor hubs
🌱 STC15L204EA — Low-voltage version
- Works down to 1.8V, perfect for battery-powered devices
- Small size, low power
- Still packs ADC, EEPROM, and PWM
🔌 Common Features Across STC15 Series
| Feature | Description |
|---|
| Core | Enhanced 8051 (single-cycle, 10x faster) |
| ISP / IAP | Yes (UART-based programming & EEPROM access) |
| Timers | Timer 0–3, 16-bit and 8-bit |
| WDT | Built-in Watchdog Timer |
| Oscillator | Internal high-speed up to 35MHz |
| Clock Source | Internal RC, external crystal or clock |
| ADC Resolution | 10-bit (on supported models) |
| PWM | Multiple channels (hardware-level) |
| I²C / SPI | Some models support I2C and SPI |
💡 Which STC15 Should You Use?
| Scenario | Recommended Chip |
|---|
| Simple blinker or LED controller | STC15F104W (super cheap) |
| Basic analog + digital combo | STC15F204EA |
| Dual UART sensor + motor system | STC15W408AS |
| Multiple serial devices (4 UART) | STC15F2K60S2 |
| Battery-powered low-voltage gadgets | STC15L204EA |
🧰 Development Tools
- Flashing Tool: STC-ISP (connect via UART1)
- IDE: Keil uVision + STC header files
- C Libraries: STC-CLib, or write pure C with register access
- Debugging: No JTAG/SWD — use UART +
printf() debugging
🛠 Sample Projects Ideas
- 💡 LED effects with PWM (STC15F204EA or W408AS)
- 🖲️ Analog joystick → UART stream (ADC + UART)
- 📡 UART-to-UART repeater (STC15F2K60S2 with 4 UARTs!)
- 🔋 Low-power sensor node with EEPROM (STC15L204EA)
Download STC15series MCU Data Sheet (English)
📡Broadcast the signal — amplify the connection.
