Stepper https://www.omc-stepperonline.com/nema-23-stepper-motor/ motors from DVDs are FOUR wire 2 phase bipolar stepper power generators. They require truly reversible voltage on each pairs belonging to the wire. You need two H bridges for each stepper motors. So total of four H bridges for two strepper motors. Some famous stepper magnetic generator controllers like ULN2003 are for the 5 wire stepper power generators, so they cannot possibly be used for controlling the particular DVD stepper motors.


You can also make your own H bridges by using 4 NPN and 4 PNP transistors and possibly TTL converters (RPi's GPIO pin number are 3. 3V so logic TTL chips might be nema 23 stepper motor required). Or you could simply buy them. There are plenty of integrated H bridge circuits available out there, such as L298. The approaches I use are L9110s Dual H Bridge purchased on Ebay (like that one: http: //www. ebay. com/itm/350877288713? ssPageName=STRK: MEWNX: IT&_trksid=p3984. m1439. l2649). They may be low cost (~$2 each), small (. 8"x1") and tend to be powerful enough (~800mA). Then again, if you buy at a Chinese seller, shipping can cost 23 days.

L9110s is also sometimes known as HG7881.

Regarding the THEY WOULD bridge, you need to ensure that the continuous current limit with the circuit is greater compared to 500mA. Usually https://www.omc-stepperonline.com/ the stepper motor in a very DVD drive is rated at 5V and each coil includes a resistance of 10ohm. To ensure the current through each coil is 500mA! A very large current!


5. a LM317 regulator, an electrical NPN bipolar transistor (like E3055, should be able to handle continuous 200mA on least), some resistors, capacitors and a number of jumpers.
The LM317 is designed for the laser driver. The facility NPN is for setting up a switch for the laser. My lab has a pile of these components so I don't have buy them. If you don't want to solder a driver by your own stepper motor personal, you can surely obtain a laser driver for <$5. The laser driver need kid output at least 200mA at 2V and possess the function of enable/disable.

In case fact, it will be a better idea replacing the NPN bipolar which includes a MOSFET transistor. There are a lot of them available and are very low-priced. Just make sure the continuous current supported through the MOSFET is above 200mA.

SOME. a solder gun, screw driver and a few basic hard wares.



STEP 1: Disassemble DVD drives (writers)
There are plenty of picture/video tutorials online due to this step so I can it short.
All you would like from www.omc-stepperonline.com/stepper-motor-driver/ the DVD are
1. stepper motor with the slider
2. Laser diodes (see picture below). Be very watchful
that the laser diodes about the DVD are very weakened.
Make sure you really don't break them.

There are other nutrients you can salvage on the DVD drive and retain for future projects, maybe a 9 V dc motor at the gate, a brushless continuous motor that spins the Dvds, some shock reducers and a few miniature lens and optic parts. You can also uncover four strong magnets nearby the laser diode. Don't dispose of them away. They will turn into useful later.

STEP A COUPLE OF: Assemble Laser
https://www.omc-stepperonline.com/stepper-motor-driver/ Now you will have two laser diodes. An example may be infrared which we don't need. The other an example may be 650nm red diode (usually carries a letter 'R' on it) and it is the one we want. The diode normally offers three pins forming any fat triangle. One is actually NC. You need a multimeter to determine which two pins are cathode and anode. The forward voltage all over anode and cathode really should be around 1. 4V plus the forward resistance should end up being 20-40k ohm. If the forward resistance is beyond their budget then the laser diode is over used.