Super simple stepper motor controller

The circuit shown above can be used to control a unipolar stepper motor which has FOUR coils (I've swiped it off an old fax machine). The above circuit can be for a motor current of up to about 500mA per winding with suitable heat sinks for the SL100. For higher currents power transistors like 2N3055 can be used as darlington pair along with SL100. The diodes are used to protect the transistor from transients.

**broken link removed**

When you say something is "shown above", it is usually a good idea to have something "above" to show!

Anyways, looks like it might come in handy.

Wow.. Nice combination of logics
I've just started the Finate State Machine lesson which involves lots of logics.

*EDIT: Just figure out it drives 2 coils each time for higher torque.

Torque stepping (energizing two coils at a time) is good.

Another alternative might be to use an 8 pin PIC microcontroller instead of the TTL logic IC and provide "Step" and "Direction" inputs. If anyone's interested I'll write the code and post it here for all to enjoy...

Mike

better post it in the forum.