MKS BC20 (7Z02481)

The MKS BC20 (7Z02481) is a single-board controller that consolidates Arduino Mega 2560 and RAMPS 1.4 functionality for 3D printer applications. This integrated architecture eliminates external board interconnects, reducing failure points while maintaining full compatibility with open-source firmware such as Marlin. The board accommodates multiple stepper motor driver types and supports a wide range of display interfaces, making it suitable for diverse printer configurations.

– Technical Specifications

Electrical
• Input voltage: 12V to 24V DC
• Power management: Specialized power chip for efficient voltage handling across full input range
• Heated bed current: Reduces by 1/4 when operating at 24V, mitigating MOSFET thermal stress
• Expansion outputs: Three 5V interfaces and three 12V interfaces

Motor & Driver Support
• Compatible stepper drivers: A4988, DRV8825, TMC2208, TMC2100
• External driver connectivity supported for higher-capacity motor control

I/O & Connectivity
• Endstop inputs: Dedicated X, Y, Z axis inputs with MOS drive circuitry and Schottky diode protection against external spikes
• Display compatibility: LCD2004, LCD12864, MKS TFT24/28/32/35/70
• Fan channels: PWM-controlled for thermal management
• Temperature sensing: Integrated measurement circuitry
• Servo interfaces: Included for accessory control

Physical & Construction
• PCB: 4-layer design for improved thermal dissipation and performance
• Dimensions: Approximately 110mm × 84mm

– Key Features

• Single-board integration eliminates wiring complexity between separate controllers
• Direct Marlin firmware compatibility with RAMPS 1.4 configurations
• Broad stepper driver support enables flexible motor control architecture
• Comprehensive protection on endstop inputs against electrical transients
• Dual voltage operation (12V/24V) with optimized current management for heated bed circuits

– Typical Applications

3D printer mainboard deployments where simplified wiring, reduced system complexity, and firmware flexibility are required.

– Compatibility & Integration

Fully compatible with Marlin firmware and RAMPS 1.4 configurations. Accepts standard stepper drivers and MKS display series without additional interface boards.