RepRap Arduino Mega Pololu Shield, known affectionately as RAMPS, is the brain for most of the 3D printers. It is designed to fit the entire electronics needed for a RepRap in one small package for low cost.
RAMPS interfaces an Arduino Mega with the powerful Arduino MEGA platform and has plenty room for expansion. The modular design includes plug in stepper drivers and extruder control electronics on a single Arduino MEGA shield. It uses Pololu Stepper Drivers delivering up to 1/16 microstepping. Four drivers are needed to move most 3D printers, with 3 going to the axis & one driving the extruder. An optional fifth stepper driver socket has been provided for additional applications.The board has 3 high power switched (By MOSFETS) outputs fused to 5 A and 11 A outputs for printbed and extruder.
The RAMPS board electronics package has following features:
Supports upto 5 stepper motor driver outputs
3 PWM controlled MOSFET powered outputs
Heated bed control and extruder control pins with 11A fuse
6 sets of Digital Pins in headers with VCC and GND for endstops
Extra pins broke out : PWM, digital, serial, SPI, I2C and analog
Standard interfaces (as that of extruder)
Reserved GCI like I2C and RS232
MOSFET 3 MOSFET are applied to the heater/ fan and thermistor circuit.
Another 5A added to protect the component parts.
A 11A fuse is added to the hotbed
I2C and SPI are reserved for expanding
Use the interface of servo motor to adjust the level of printing platform automatically.
Adding a SD module for SD ramps module.
LED can indicate the status of the heater (the open and close of MOS).