80V 7A Drive Unipolar Micro CONTROLLER LS7290

[irving2008]

Mariss,

I am inclined to agree with you on the 'make it yourself front', and I usually do so where it makes sense - at least that way you know exactly how it works. Having said that, I also recognise that some people have limitations on skills, budget and/or time (in my case its usually the latter two) and would like to find some of the more difficult bits 'done for them'. Hence when a chip comes along that seems to offer good things people jump on it... not always understanding the limitations. Although to be fair to LSI they did make this limitation clear in the data sheet and the app note so no one should have gone ahead and invested time without understanding the limitation. The main and only advantage of the LS7290 over the L297 in the majority of systems is simply price.

[mrgadgeteer]

Can someone suggest a decent open source design that will run unipolar motors using Mach3 or equivalent software? I've been tinkering with IRF540 MOSFETs switched by my BS2 and a Slo-Syn M063-FD09 with little success. They drive little scanner size pancake motors perfectly fine but when the heftier Slo-Syn is attached the 540's appear to stay "on". A very slight pulse does get to the motor. I'm using regulated 12V and current limited to roughly 2 amps by a light bulb on the motor side. This motor wants almost 5 Amps but I'm afraid to push to the 540's envelope just yet.

I only have a basic understanding based on my own "trial & error hacking" so it's not difficult for my eyes to glaze over with all the the techno intricacies, design errors etc. discussed. This is fun but confusing, I sure could use a mentor!

Thanks
Mike

[H500]

Originally Posted by mrgadgeteer Can someone suggest a decent open source design that will run unipolar motors using Mach3 or equivalent software?

See post 116 here:
http://cnczone.com/forums/showthread...=81125&page=10