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Driving a Hewlett- Packard Stepper Motor? Answered

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I am just getting my feet wet and have been doing a little research on stepper motors. 

I pulled two good- sized steppers from an HP printer a couple months ago, but I haven't been able to run them yet. 

I want to use an EasyDriver[https://www.sparkfun.com/products/retired/10267] to drive them, but due to the imposing ICs, I'm hesitant to just plug in the cables like a standard stepper. (I have identified one of the ICs(AN44050A) as a stepper controller)

Any recommendations on how to drive this puppy from a BeagleBone Black or other 3.3v logic controller?


6 Replies

steveastrouk (author)2014-11-27

That's a stepper with an integrated driver. Best thing would be to trace out the incoming wires and drive the chip on board.

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rene-vile (author)2016-02-23

it is a 3-phase brush-less dc motor with what looks like a sinusoidal driver... cant help you with the ic but i know the motor.

the three sop8 chips are propably rk4936 witch you can find tha datasheet on and pwm drive the motor.

motor voltage ic 24v

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Wired_Mist (author)rene-vile2016-02-23

Brosing though the Archives eh? :P

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rene-vile (author)Wired_Mist2016-02-24

i just fell over this in my search for that illusive an44050a chip, and since i know what the motor is i thought i would help the next person hunting the same answer... :)

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Wired_Mist (author)2014-11-27

Yhea this looks like a brush-less motor. Thats Alot of circuitry for a Stepper driver. I Really Wish you had included a pic of the wires coming out and the pin-out; possibly what they were hooked into? Then you would be able to tell what it is.

If it is indeed a Stepper, Then Go with Steve up there !

Either way the board is Specifically designed to run the motor. No need to re-invent the wheel; Just use it :P

We'll all be be waiting for your Pic/Responce! Good luck :D

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liquidhandwash (author)2014-11-27

I dont think what you have there is a stepper motor, It looks more like a brushless dc motor. You maybe able to get it to run by hooking it up to a battery. Look near your leads on the PCB it may have some clues as to how to power it up. If there are no markings on the board, trace the tracks a to a capacitor. your looking for + and - . you might find that the red and black leads are the + and - . Hook those up to a 9 volt battery and experment with the other leads. You may find that earthing a lead or putting power to it will turn it on.

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