2.5A Bipolar Stepper Driver with Micro-Stepping, Current and Decay Control – Arduino Compatible

This is an Arduino compatible board that contains an Atmega328 microcontroller and Bipolar Stepper Motor Driver chip STK682-010. This Hybrid IC from ON Semiconductor can deliver up to 2.5A current and it can have an input supply up to 32V DC. It has multiple micro-stepping options such as Full step, 1/2th Step, 1/4th Step, 1/8th Step, 1/16th Step, 1/32th Step, 1/64th Step, 1/128th Step.  PR1 trimmer potentiometer is provided to set the decay, 3.5V Slow Decay, 1.1V to 3.1V Mixed Decay, 0.8V-1V Fast Decay, and PR2 Trimmer Potentiometer provided to set the output current. Chopping frequency set to 83.3 Khz using capacitor C5 100PF. Micro-Stepping can be set with the help of jumper J1, J2, J3. This board is by default enabled since the enable pin has a pull-up resistor, but you can provide a low signal to disable the motor driver chip. Atmega328D provides Direction pulse, Step pulse, Enable control, etc. The IC has built-in automatic half current functions to reduce the vibrations & current while the motor is in static mode. It is important to use a heatsink on the motor driver chip. Refer to the micro-stepping table to set the micro-stepping. Board requires a Motor power supply as well logic supply 5Vdc.

Arduino Programming

Arduino code is provided to test the board. The user will be able to control stepper motor speed using a 10K potentiometer connected to Analog pin A0 using connector U3. Users may write their own code to drive the motor as per requirements, micro-stepping is separate and independent from micro-controller. Only Pulse/Clock input, Direction, enable pins are connected to Arduino hardware.

A new Atmega328 requires bootloader programming and Arduino code, refer to the link below for more information:

https://www.arduino.cc/en/Tutorial/BuiltInExamples/ArduinoToBreadboard

Arduino Pins

• Digital Pin D6: Enable STK682-010, Default this pin is High Using Pull-up Resistor R9, Pull Down this Pin to disable the motor driver
• Digital Pin D5: Clock/Pulse STK682-010
• Digital Pin D10: Dir (Motor CCW/CW Low or High) STK682-010, Default this Pin is High Using pullup Resistors R3
• Analog Pin A1: Analog input, Potentiometer or Sensor Connection

Features

• Supply Voltage Range 9-32V DC (Connector CN1)
• Logic Supply 5V DC (CN4 Pin 4=GND, Pin 5=5V DC Input)
• Motor Load 2.5A Continues (Connector CN2)
• J1, J2, J3 Jumpers for Micro-Stepping
• PR2 Current Adjust Trimmer Potentiometer
• PR1 FDT Trimmer Pot to adjust Decay
• Built-In Automatic Half Current Maintenance energizing function
• Built-in Over Current Protection Circuit (Within IC)
• Built Thermal Shutdown Circuit (Within IC)
• On-Board Power LED D1
• PCB Dimensions 57.94 x 46.67 mm

Schematic

Parts List

Connections

Micro Stepping

Gerber View

Photos

Video

STK682-010 Datasheet