Designs for open source consideration

[pminmo]

http://webpages.charter.net/pminmo/cncelectronics.htm

Just added a Opto isolated BOB compatable with the driver boards. Looking for a second set of eyes to review.

Thanks,
Phil

[davesaudio]

values for the passives?

[pminmo]

thanks, updated.

[tachus42]

see the post here http://www.cnczone.com/forums/showth...1365#post41365
about the unipolar driver board.
For the break out board the 6n135 datasheet gives a worse case current transfer ratio of 5% . So you need to change the resistor in series with the led of the opto to 150 Ohms and the output resistor needs to be 6800 for reliable operation. Or you could use a darlington optocoupler like a 6n138.
They might be harder to find but opto's in dual or quad packages would probably work out cheaper and simplify the board layout.

[pminmo]

Great work tachus42 on the unipolar board. The reason I put the trasistor in was for inversion wanted the led to illuminate on high. I'll upload them.

Will look at the BOB.

Thanks,
Phil