Is it possible to use a stepper motor without a micro-processor ?

[zms]

well i guess the title says it all .

i was toying with the idea that the leads of the motor can be connected to logic gates and relays and etc etc, and hence spare the trouble of getting a microprocessor and programming stuff.

what say ?

 

[davenn]

yes, it is, did that years ago, long before microcontrollers existed

 

[Bluejets]

I used to recycle the boards out of an old floppy drive as they provided what is required. Then just add the step and direction signals. Bit hard to come by these days but surely a chip with the same properties exists.

 

[davenn]

I used to recycle the boards out of an old floppy drive as they provided what is required. Then just add the step and direction signals. Bit hard to come by these days but surely a chip with the same properties exists.

with a bit of rigging, steppers and their drives from printers and similar gear also can be put into use

 

[Alec_t]

Googling "stepper driver IC" gives lots of hits for suitable control chips.

 

[zms]

I used to recycle the boards out of an old floppy drive as they provided what is required. Then just add the step and direction signals. Bit hard to come by these days but surely a chip with the same properties exists.

can you give me more info on this ?

 

[Bluejets]

Currently away from my files/computer (Beer Leo$2.00 a tallie....land of smiles) but this one might get you started..... epanorama.net ...... How to use disk drive stepper motors....

 

[BobK]

You can, but the circuit is way more complex without a microcontroller.

Bob

 

[Minder]

You also need to check whether the steppers are bi-polar or unipolar which determines the commutation method.
M.

 

[hevans1944]

All you need to drive a stepper motor is a quadrature clock, which can be obtained from two D-type flip-flops. Add some transistor drivers for the motor coils and a clock oscillator for the flip-flops and ... Voila!

Back in the day, before PWM became popular, we did this with hundred volt power supplies switching high-voltage power transistors with the motor windings in series with large power resistors so the resistance swamped the motor reactance. Dissipated more power in those resistors than we did in the motor, but it worked and had plenty of torque. Only computer in sight was a mainframe attended by IT priests in white coats, all protected by glass windows and enough air conditioning to refrigerate a good sized beer truck.

 

[BobK]

All you need to drive a stepper motor is a quadrature clock, which can be obtained from two D-type flip-flops. Add some transistor drivers for the motor coils and a clock oscillator for the flip-flops and ... Voila!

That depends on what you mean by "drive". This minimalist driver will allow you to run the motor, but not to count steps for positioning for instance.

Bob