Features: 1. Drive current algorithm: i = vref* 1.9/2.5, default Verf is about 0.65V, So the default current is 0.5A and the maximum current is 1A. 2. Verf measure Gnd and the voltage at the middle of the potentiometer. 3. The usage of driver module: When using on Ramps1.4 or MKS Gen, or Loco touch screen board, please remove the 3 jumper caps under the socket. pay attention to the direction, heatsink can stick on the surface of PCB. 4. The motor direction is opposite to A4988 and DRV8825, adjust the firmware or motor wire sequence if want to change 4988. If you use the lego board, please set the motor direction directly on the touch screen. Set the direction from inside. 5. Usage of driver module used on the lego board: Remove the 3 jumper caps under the jack, module has no subdivision settings, the value is calculated according to 16 subdivision. Using the difference algorithm to extend 16 subdivision to 256 subdivision of the chips inside. Specification: Condition:100% Brand New Material: ABS Color: As Pictures Shown Type: TMC2208, TMC2100, TMC2130(optional) TMC2208: approx.8*12cm/3.2*4.7in TMC2100: approx.5*10cm/2*3.9in TMC2130: approx.8*8*2cm/3.1*3.1*0.8in Weight: Approx.7-12g Package list: 1 * Stepper Motor Driver 1 * Accessory Note: 1. Do not connect the motor when measuring the voltage, or it will easily burn the drive. 2. Measure the voltage should be connected to the power supply, not only connected to the USB power supply. 3. Please pay special attention to the direction, do not insert reversedly.