28mm Hybrid Stepper Series

The 28mm Hybrid Stepper Motor Series combines a compact form factor with a hybrid stepper construction. Combine with a microstepping driver to reduce vibration and achieve higher step resolution. Choose a baseline version or request your own customized configuration.


  • Bipolar or unipolar versions available
  • Hybrid stepper construction
  • Available in single or double shaft versions
  • CE and RoHS approved
  • Customizations on request

Step Angle 1.8° (±5%@ full step, no load)
Resistance Accuracy ±10%
Inductance Accuracy ±20%
Temperature Rise ≤80K
Ambient Temperature -20°C to 50°C
Shaft Radial Play ≤0.02mm @ 450g-load
Shaft Axial Play ≤0.02mm @ 450g-load
Max Radial Force 28N @ 20mm from flange
Max Axial Force 10N
Dielectric Strength 500V for one minute
Insulation Resistance ≥100MΩ, 500VDC
Holding Torque 0.43 to 1.2 g⋅cm

There are several important criteria to consider: holding torque, physical size (NEMA size, length of motor etc.), supply voltage, and supply current etc. Once you determine these key criteria, we can find a suitable model for you. Feel free to contact us, we are more than happy to help you with the selection process.

Certainly, most of our customers request custom configurations in one form or another. If you plan on replacing a motor in an existing application, just send us a drawing or sample and we can help you find a suitable replacement. Alternatively, contact us and describe your application, our engineers will work with you to create a tailor-made solution.

We stock many of our standard models. If you would like to test a sample first, we are glad to send some your way. Of course we do not stock specialized motors. If you have special needs, please let us know and we will try our best to send you samples as soon as possible.

If you are ordering samples of standard models, we can usually have them shipped and delivered within 5 days by air. When requesting custom motors, please allow us a 4-5 week lead-time.

We are very flexible with shipping and have dealings with most major courier services around the world. When placing an order, simply provide us a shipping address and contact information, we will handle the rest. If there is a forwarder or courier you prefer to use, just let us know and we will accommodate.

Delivering quality products is an absolute priority for us at LDO. We have test procedures throughout the manufacturing process starting from individual components. If you need a specialized motor from us, we also augment our existing test plans with custom testing solutions. In the rare case that an issue does arise, we will work with you to solve any problems in a timely and transparent manner.

Yes, we can provide OEM services for volume production. Feel free to talk to us about your branding needs.

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The following are common submodels for the LDO-28STH series. Click to request a quote and/or more information on a specific submodel.

Rated Voltage Current /Phase Resistance /Phase Inductance /Phase Holding Torque Num. Leads Rotor Inertia Approx. Weight Body Length
Part No. (V) (A) (ohm) (mH) (kg⋅cm) () (g⋅cm^2) (kg) (mm)
LDO-28STH32-0956 2.66 0.95 2.8 0.8 0.43 6 9 0.11 31.5
LDO-28STH32-0674 3.8 0.67 5.6 3.4 0.6 4 9 0.11 31.5
LDO-28STH45-0956 3.4 0.95 3.4 1.2 0.75 6 12 0.14 44.5
LDO-28STH45-0674 4.56 0.67 6.8 4.9 0.95 4 12 0.14 44.5
LDO-28STH51-0956 4.4 0.95 4.6 1.8 0.90 6 18 0.2 50.5
LDO-28STH51-0674 6.2 0.67 9.2 7.2 1.2 4 18 0.2 50.5