unipolar vs bipolar driver

[khite]

Ok so I am at a crossroads and I figured you guys could help me out. I am looking for the following in a driver:
-microstepping
-perferably high amperage to allow upgradability of the motors

I have been using pminmo.com as my resource since he has a very good layout of designs and has been very helpful lately. So here are the choices I am looking at:

1. Bipolar driver such as the A3977 or the PICstep but will only allow me 3A, so I won't be able to upgrade to a larger motor in the future if I want.

2. Unipolar driver such as Mardus-Kreutz which allows upto 8A so it will power larger motors when I go bigger.


So is bipolar that much nicer for me to stay at a low amperage with no upgradability.

If there are any other options please let me know.

Thanks

[RomanLini]

A3977 is really only suitable for 2A in continuous machine use. It's really a little SMD driver for use in bubblejet printers and other low duty applications.

A larger more rugged unipolar IC such as the SLA series will support 3A at continuous use, and have a proven track record for reliability. You also get the benefit of better high speed performance than bipolar series and less resonance than bipolar parallel.

My personal recommendation is the SLA7062 as used in this high performance unipolar driver;
SLAmStepper

[khite]

Ok so if I go unipolar, is the new Linistepper better than the sla7062 driver?

[Jesse B]

Ok so if I go unipolar, is the new Linistepper better than the sla7062 driver?

The Linistepper can only run, ideally, around 1.5A-2A. The SLAm Stepper can run up to 3A. It depends on the motors you go with. The Linistepper will also probably run a bit smoother, but again, they can handle less amperage.


- Jesse