A4982 Stepper Driver Trouble

I have made a board based on the BigEasy Driver found at Sparkfun. But instead of the A4983, I used an A4982, which is basically the same but comes in a package that I can hand solder.

Anyway, when I hook up my bench supply and bring it up to around 11V, it jumps to saying it's putting out 3A and the GND wire starts heating up (I didn't let it get past warm). I checked at the screw terminals I have on the board with a meter and it's says less than a volt. Seems I have a short somewhere.. But, I have checked over the board and I have no solder bridges, etc..

I found the problem, was a bad board design on my part. But I hacked the board and fixed that problem, but now the LM317 gets hot as you-know-what and no movement out of the stepper.. Think I may just buy an EasyDriver from sparkfun just to get the damn stepper turning..

So, would someone check over my schematic and see if I got something screwed up. I copied the Big Easy schematic from sparkfun.

Also, I have the Arduino like the pic at this link: http://bildr.org/2012/11/big-easy-driver-arduino/

//This is an example of how you would control 1 stepper

#include <AccelStepper.h>

int motorSpeed = 9600; //maximum steps per second (about 3rps / at 16 microsteps)
int motorAccel = 80000; //steps/second/second to accelerate

int motorDirPin = 2; //digital pin 2
int motorStepPin = 3; //digital pin 3

//set up the accelStepper intance
//the "1" tells it we are using a driver
AccelStepper stepper(1, motorStepPin, motorDirPin);



void setup(){
stepper.setMaxSpeed(motorSpeed);
stepper.setSpeed(motorSpeed);
stepper.setAcceleration(motorAccel);

stepper.moveTo(32000); //move 32000 steps (should be 10 rev)
}

void loop(){

//if stepper is at desired location
if (stepper.distanceToGo() == 0){
//go the other way the same amount of steps
//so if current position is 400 steps out, go position -400
stepper.moveTo(-stepper.currentPosition());
}



//these must be called as often as possible to ensure smooth operation
//any delay will cause jerky motion
stepper.run();
}

Stepper Driver.sch (971 KB)

Have you measured all the voltages and currents relevant to the LM317? That's probably a first diagnostic step.

Thanks for replying Mark.

I didn't realize anyone responded as the forum is being buggy and didn't receive any notifications. But, I have to admit the forum is running lightning fast now.

I fixed the 317 overheating issue. It was a bad solder joint one of the resistors.

I am getting 24V @10mA to the LM317 and 5.2V to the driver IC.
At the stepper I am getting 24V @75mA, Which is obviously too low.

Other info I should have included:

  • Type 17PM-J034-P2VS
  • Minebea Co. LTD.
  • Part# FH5-1043
  • 1.8 deg 200 steps/rev when full-stepping
  • 2 Phase @ 2A per phase

Datasheet for the 17PM-J series.

When I first bought these motors and started digging for information, I concluded these were bi-polar, now I am beginning to think they are uni-polar..

Any feedback is very much appreciative.

How many wires on your stepper?

4 = bipolar only
5 = unipolar only
6 = bipolar or unipolar, depending on wiring
8 = bipolar or unipolar, depending on wiring

6 pins, but 4 wires coming out. I am guessing that the unwired pins are the commons.

PIN1= B-
PIN2= B Common (no wire)
PIN3= B
PIN4= A
PIN5= A Common (no wire)
PIN6= A-

This is the first time playing with steppers. I am probably just going to get the BigEasyDriver board from Sparkfun just to get the code and steppers working. I may have damaged the A4982 IC on my board..