Shenzhen BIGTREE technology co., LTD.

Operation Manual of the Motherboard 



BTT SKR MINI E3 V2.0 is a customized motherboard for Ender3 printer launched by the 3D printing team of Shenzhen BIGTREE technology co., LTD., which can perfectly replace the motherboard of the original Ender3 printer.

Motherboard features: (mainly introduces upgrades based on V1.2)

  1. Use MP1584EN power chip, support 12-24V power input, the maximum output current can reach 2.5A;
  2. The hotbed MOS tube uses WSK220N04, low on-resistance, larger heat dissipation area, and reduce heat generation;
  3.  Onboard Sensorless homing function, which can be used by plugging in the jump cap;
  4. Optimize the PCB board and frame to avoid the phenomenon of screw hole gap and screws hitting components;
  5. Support touch, filament detection, BTT UPS 24V V1.0, BTT Relay V1.2, etc .;
  6.  Onboard EEPROM: AT24C32;
  7. Add parallel double Z-axis interface;
  8. Increase the board layer: 4 layer board;
  9. Increase the heat dissipation area of the back driver and strengthen the heat dissipation capacity;
  10.  Two CNC fan interfaces;
  11. Increase the distance between the driving chip and the components to avoid the trouble caused by the heat sink;
  12. Add protection device to the thermistor interface;
  13. 5V power supply with BLtouch, TFT and RGB interfaces is optional;
  14. The driver shares a physical UART port, which saves IO and enhances stability.

Motherboard parameters:

Appearance size: 100.75 * 70.25mm
Installation size: check BTT SKR MINI E3 V2.0-SIZE.pdf for details
Layer: 4 layers
MCU: ARM Cortex-M3 STM32F103RCT6
Power input: DC 12 / 24V
Logic voltage: 3.3V
Motor driver: UART mode of onboard TMC2209;
Motor drive interface: XM, YM, ZAM, ZBM, EM
Temperature sensor interface: TH0, THB, 2 channels 100K NTC (thermal resistance)
Display: 2.4 inch TFT, 3.5 inch TFT, Ender3 original LCD12864 screen, etc.
PC communication interface: mini-USB-B type, easy to plug and unplug, communication baud rate 115200
Support file format: G-code
Recommended software: Cura, Simplify3D, pronterface, Repetier-host,

Description of motherboard indicators

After power on the mainboard:
3.3v red light is power indicator: the red light is on, indicating normal power supply;
Status red light is the Status indicator: when updating the firmware, it will flicker.
D8 green light is the HB status indicator for the hotbed: it is always on when heated, and it goes out when not heated.
D6 green light is the indicator light of E0 status of the heating tube: it is always on when heating, and it will go out when not heating.
D10 green light for CNC fan FAN0 status indicator: it lights up when turned on, and goes out when turned off.
D7 green light for CNC fan FAN1 status indicator: it lights up when turned on, and goes out when turned off.

Communication between motherboard and PC

The motherboard communicates with the PC (Windows system) through the [USB] interface. Before communication, the driver needs to be installed to be used normally. Driver acquisition method: Website: Download the file named:

mapleDrv to install it.

BIGTREETECH SKR Mini E3 V2.0 - mapleDrv to install it

Interface Instruction

  1. Motherboard Size Diagram
    WWW.BIGTREE-THCH.COMBIGTREETECH SKR Mini E3 V2.0 - Interface Instruction
  2. Motherboard Wiring Diagram
    BIGTREETECH SKR Mini E3 V2.0 - Wiring Diagram
  3. Sensorless Homing Function Selection:
    BIGTREETECH SKR Mini E3 V2.0 - Function Selection
    As shown in the figure, the Sensorless homing function can be used to connect the corresponding axis with the jumper cap.
    Note: if you select this feature, you cannot use external ENDSTOP!!
  4.  5V power selection for BLtouch, TFT, and RGB interfaces:
    1) onboard +5V power supply:
    BIGTREETECH SKR Mini E3 V2.0 - RGB interfaces 2)Use BIGTREETECH DCDC5V V1.0 module+5V power supply:
    BIGTREETECH SKR Mini E3 V2.0 - power supply
  5. Connection with BIGTREETECH Relay V1.2:
  6. Connection with BTT UPS 24V V1.0:
  7. Connection with Neopixel lights:
    BIGTREETECH SKR Mini E3 V2.0 - Neopixel lights
  8. Connection with touch:
    BIGTREETECH SKR Mini E3 V2.0 - with BLtouc

The firmware description of the motherboard

The factory motherboard is installed equipped with firmware for testing (model Ender3), which can be used directly or changed according to your own needs.

  1. The Firmware Acquisition Method of Motherboard:
    Obtain by Ask customer service or technical personnel;
    Download at our Company Open source website:
  2. Motherboard Firmware update method
    Choose the file suitable for your model in the downloaded firmware package to copy to SD Card Root directory.
    Note: Filename cannot be changed, firmware.bin must be lowercase!
    Insert SD card into the mainboard SD card slot, re-energize or press the reset key, wait for about 10S. After that, the update can be completed.
  3. For DIY motherboard firmware, please refer to BTT SKR MINI E3 V2.0-PIN.pdf data.


  1. Firmware file names in SD Card cannot be changed.
    (including both upper and lower case letters).
  2. The wiring process and the plug-in drive process must be carried out under the premise of power off. The power-on can be started after checking the correct connection of the line and the correct insertion of the drive, so as to prevent the wrong connection of the mainboard and drive from being burnt down and causing unnecessary losses.
  3. The E3 motherboard can support the LCD12864 screen with the interface CR10_STOCKDISPLAY.

If you encounter other problems, please contact us. We will definitely answer your questions patiently. If you have any good suggestions on our products, please give us feedback. We will consider them seriously. Thank you for choosing BIGTREETECH products!

Documents / Resources

BIGTREETECH SKR Mini E3 V2.0 Motherboard [pdf] User Manual
SKR Mini E3 V2.0 Motherboard


Join the Conversation


  1. Hello, could you give me some information on how to plug in the additional power module and also how to connect the LEDs. thank you so much
    Bonjour, pourriez vous me donner des informations pour brancher le module d’alimentation additionel et aussi sur la façon dont connecter les LED. Merci beaucoup

  2. The processor of my BTT SKR mini E3 V2.0 card burned down (STM32F103RCT6), I changed it, but I cannot use it because there is no operating system, how can I install an operating system to activate the card (no firmware)
    STM32F103RCT6 working system need..
    BTT SKR mini E3 V2.0 kartımın işlemcisi yandı (STM32F103RCT6) değiştirdim fakat işletim sistemi olmadığı için kullanamıyorum nasıl işletim sistemi yükleye bilirim kartı aktif etmek için (no firmware )
    STM32F103RCT6 working system need..

  3. The processor of my skr mini e3 v2.0 card burned down. I replaced the stm32f103rct6 with a new one, but the card does not work because there is no operating system. Can you help me how can I program stm32f103rct6? What is the operating system?
    skr mini e3 v2.0 kartımın işlemcisi yandı stm32f103rct6 yenisi ile değiştirdim fakat işletim sistemi olmadığı için kart çalışmıyor bana yardımcı olurmusunuz stm32f103rct6 nasıl programlayabilirim işletim sistemi ne?

Leave a comment

Your email address will not be published.