EMAX 4.3g Digital Servo Pastic Gear 0.8kg Torque for 3D F3P Airplanes – ES9051

• Simple step and direction control interface
• Six different step resolutions: full-step, half-step, 1/4-step, 1/8-step, 1/16-step, and 1/32-step
• Adjustable current control lets you set the maximum current output with a potentiometer, which lets you use voltages above your stepper motor’s rated voltage to achieve higher step rates
• 45 V maximum supply voltage
• Built-in regulator (no external logic voltage supply needed)
• Can interface directly with 3.3 V and 5 V systems
• Over-temperature thermal shutdown, over-current shutdown, and under-voltage lockout
• Short-to-ground and shorted-load protection
• layer, 2 oz copper PCB for improved heat dissipation.

It is designed to fit the entire electronics needed for a RepRap in one small package for low cost. RAMPS interfaces an Arduino Mega/SainSmart Mega with its powerful platform and has plenty room for expansion. The modular design includes plug in stepper drivers and extruder control electronics on an Arduino Mega/Sainsmart MEGA shield for easy service, part replacement, upgrade-ability and expansion. Additionally, a number of Arduino expansion boards can be added to the system as long as the main RAMPS board is kept to the top of the stack.