# BigTreeTech SKR Mini E3 V1.2

> Ultra-quiet 32-bit 3D printer board with 4 integrated TMC2209 UART stepper drivers. STM32F103RCT6 @ 72MHz. Direct drop-in replacement for Ender 3. Supports Marlin and Klipper.

## Quick Facts

- **Brand:** BigTreeTech
- **Board Type:** 3D Printer Control Board
- **Price:** ~$38.99
- **Product Readiness:** consumer
- **CPU:** STM32F103RCT6
- **CPU Architecture:** ARM Cortex-M3
- **CPU Cores:** 1
- **RAM:** 48KB
- **Flash:** 256KB
- **USB:** USB Micro-B
- **Power:** 12-24V DC
- **Operating Voltage:** 3.3V
- **SD Card:** MicroSD

## Open Source

- **Firmware:** Yes
- **Schematics:** Yes
- **PCB Layout:** Yes

## Compatible Firmware

Marlin, Klipper

## Use Cases

- 3D Printing

## Components

- **STM32F103RCT6** (MCU): STMicroelectronics STM32F103RCT6 32-bit ARM Cortex-M3 microcontroller, 256KB flash, 48KB RAM, running at 72MHz — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.st.com%2Fresource%2Fen%2Fdatasheet%2Fstm32f103rc.pdf&ref=openhardware.directory&product=bigtreetech-skr-mini-e3-v1-2&source=md-export)
- **TMC2209 (integrated x4)** (Stepper Driver): 4x TRINAMIC TMC2209 stepper drivers integrated directly on the PCB with UART mode, StealthChop2, and stallGuard for sensorless homing — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.trinamic.com%2Ffileadmin%2Fassets%2FProducts%2FICs_Documents%2FTMC2209_Datasheet_V103.pdf&ref=openhardware.directory&product=bigtreetech-skr-mini-e3-v1-2&source=md-export)
- **MicroSD slot** (Storage): MicroSD card slot for firmware updates and standalone print file storage — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fbiqu.equipment%2Fproducts%2Fbigtreetech-skr-mini-e3-v1-2-32-bit-control-board-tft35-e3-v3-0-integrated-tmc2209-uart-for-ender-3&ref=openhardware.directory&product=bigtreetech-skr-mini-e3-v1-2&source=md-export)

## Protocols

- **UART**
- **SPI**
- **I2C**
- **USB**

## Description

The BigTreeTech SKR Mini E3 V1.2 is a compact 32-bit control board specifically designed as a direct drop-in replacement for the Creality Ender 3's original 8-bit mainboard. It uses the STM32F103RCT6 ARM Cortex-M3 processor running at 72MHz and features 4 integrated TMC2209 stepper drivers in UART mode for silent operation — no separate driver modules required.

The board supports Creality's Ender 3, Ender 3 Pro, CR-10, and CR-10 Mini printers out of the box. Integrated TMC2209 drivers offer StealthChop2 for near-silent printing, plus stallGuard for sensorless homing. A BLTouch/CR Touch header is included for auto bed leveling.

The SKR Mini E3 V1.2 accepts 12–24V DC input, includes a MicroSD card slot, USB Micro-B for PC communication, and expansion headers for TFT displays. Full schematics, PCB layouts, and pre-configured Marlin firmware builds are available on GitHub. Klipper is also fully supported.

## Where to Buy

- [BIQU Equipment](https://openhardware.directory/r?to=https%3A%2F%2Fbiqu.equipment%2Fproducts%2Fbigtreetech-skr-mini-e3-v1-2-32-bit-control-board-tft35-e3-v3-0-integrated-tmc2209-uart-for-ender-3&ref=openhardware.directory&product=bigtreetech-skr-mini-e3-v1-2&source=md-export) — $38.99

## Resources

- [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2Fbigtreetech%2FBIGTREETECH-SKR-mini-E3&ref=openhardware.directory&product=bigtreetech-skr-mini-e3-v1-2&source=md-export)
- [product](https://openhardware.directory/r?to=https%3A%2F%2Fbiqu.equipment%2Fproducts%2Fbigtreetech-skr-mini-e3-v1-2-32-bit-control-board-tft35-e3-v3-0-integrated-tmc2209-uart-for-ender-3&ref=openhardware.directory&product=bigtreetech-skr-mini-e3-v1-2&source=md-export)

## Tags

`3d-printer`, `control-board`, `stm32`, `marlin`, `klipper`, `bigtreetech`, `open-source`, `32-bit`, `tmc2209`, `ender-3`, `mini`, `integrated-drivers`

## Images

![BigTreeTech SKR Mini E3 V1.2](https://nbg1.your-objectstorage.com/openhardware-directory/entities/bigtreetech-skr-mini-e3-v1-2/0b7da40cf797.jpg)
![BigTreeTech SKR Mini E3 V1.2](https://nbg1.your-objectstorage.com/openhardware-directory/entities/bigtreetech-skr-mini-e3-v1-2/0450ea065636.jpg)
![BigTreeTech SKR Mini E3 V1.2](https://nbg1.your-objectstorage.com/openhardware-directory/entities/bigtreetech-skr-mini-e3-v1-2/b002343a70dc.jpg)
![BigTreeTech SKR Mini E3 V1.2](https://nbg1.your-objectstorage.com/openhardware-directory/entities/bigtreetech-skr-mini-e3-v1-2/a221e2aa92bd.jpg)

---
[View full device page](https://openhardware.directory/devices/bigtreetech-skr-mini-e3-v1-2)