L293D control 5 wire stepper motor?

Other Hardware Motors, Mechanics, Power and CNC
1

The stepper I brought yesterday has 5 wires (5v 28YBJ-48), some of the tutorials on the web can use L293D to drive a stepper motor, but they ALL use 4 wire ones. My motor has an extra red wire, the datasheet said the red wire is common wire, I tried to wire it to the common ground but the motor's still not working.

I wired the motor to arduino as below schematic from http://tmmbach.net/2010/08/05/driving-a-bipolar-stepper-motor-forward-and-backward-with-l293d-or-sn754410/

2

Where is the link to "The stepper I brought yesterday has 5 wires (5v 28YBJ-48)" ??

3

http://arduino-direct.com/sunshop/index.php?l=product_detail&p=120


This is the one have now!

4

What you have is a unipolar stepper motor, and the L293D and similar H-bridge chips are for bipolar stepper motors. See the unipolar stepper circuit at http://arduino.cc/en/Tutorial/MotorKnob.

[EDIT: that circuit uses darlington drivers, but I prefer to avoid Darlingtons - especially when the supply is as low as 5v - because of their high saturation voltage. You could use four NPN transistors with 470 ohm base resistors instead; or four 2n7000 mosfets.]

5

Hi,
The information on this motor is here:
http://arduino-direct.com/sunshop/index.php?l=product_detail&p=120

And some how-to for these motors is here:
http://arduino-info.wikispaces.com/SmallSteppers

These are typically driven from 4 darlington type transistors or their equivalent in a chip like the ULN2003 shown here:
http://arduino-direct.com/sunshop/index.php?l=product_detail&p=172

More overall info on steppers here:
http://arduino-info.wikispaces.com/StepperMotors

DISCLAIMER: Mentioned stuff from my own shop...

6

To summarise steppers come in 4, 5, 6 and 8 wire versions.

4 - bipolar only
5 - unipolar only (*)
6 - unipolar/series-bipolar
8 - unipolar/series-bipolar/parallel-bipolar

You have the one sort that doesn't work with bipolar drivers (in theory). However all is not lost - so long as you only drive on phase at a time and keep the fifth wire unconnected, you may get it to work. Do not connect the common wire to ground at all for bipolar use.