Introduction

Mellow Fly-D8 is a high-performance 3D printer motherboard developed by the Fly3D motherboard R&D team at Guangzhou Mellow Electronics Technology Co., Ltd., supporting up to 8 stepper motors.

Product Features

• The motherboard has isolated 5V power supply protection for limit switch and other interfaces; no power will be output if the POWER supply is not connected
• Features a 32-bit ARM Cortex-M7 series STM32H723 microcontroller chip with a main frequency of 550MHz
• Supports CAN bus and RS232 connections, providing more stable data transmission, lower latency, and more reliable connections
• The motherboard includes BOOT and RESET buttons, allowing users to update firmware via USB in DFU mode
• Power interface has reverse polarity protection to prevent damage caused by incorrect wiring during DIY installation
• Provides two USB 2.0 interfaces, expanding connectivity options; one of the USB interfaces can be switched to an RS232 interface via a toggle switch to accommodate various device connection needs

Product Specifications

• Microcontroller: 32-bit ARM Cortex-M7 series STM32H723 microcontroller with a main frequency of 550MHz
• Firmware: Marlin 2.0/Klipper
• Driver mode support: TMC: UART/SPI
• Eight drivers supported: A4988, LV8729, DRV8225, TMC2208/2209/5160, etc.
• Display: Serial touchscreen, mini12864 LCD, 12864 LCD, 2004 LCD, FLY 4.3/7.0 V1
• Supports auto-bed leveling sensors: BLTouch, PL08N proximity sensors, Klicky, Voron Tap, etc.
• Input voltage: supports 12V/24V
• 6 limit switch interfaces, enabling precise range limitation and position control
• 2 RGB interfaces for vibrant visual effects
• 3 heater cartridge interfaces, providing independent control for extruders and heated beds
• 4 thermistor interfaces, capable of monitoring up to four temperature groups simultaneously for precise temperature control
• USB interface: supports two USB 2.0 interfaces, one of which can be switched to RS232 via a toggle switch
• Provides two USB 2.0 interfaces, expanding connectivity options, one of which can be switched to an RS232 interface via a toggle switch to accommodate various device connection needs

Notes

Output Port	Maximum Current at 24V	Maximum Current at 12V
Bed Port	10A	5A
Heater Port	6A	3A
Fan Port	1A	0.5A