Help! DIY 4 amp L297/6203 driver

[Ross77]

they are zener diodes. You need a total voltage of Vclamp - 1.4. By using 2 diodes you can get a bit more fine tuning of the voltage, for example a 30v and a 7.5would give a clamp of 30 + 7.5 + 1.4 = 38.9 which would be good for a 36v supply on 40V drivers...

Thanks. My supply is 41.5V unloaded so will this still work? or wil i need to up it to a 30+10? Im not to good with diodes, can you recomend a suitable part?

I've tweaked the schematic a bit to make the board a bit more sensible in layout.

That makes sense, I'll do that in the future. I think the resistors where 180deg out because i swapped the pins (vertical mount) in the pcb editor to make the lay out easier. i'll have to look out for that as I didnt think it also changed the schematic.....

Hands up about the connectors as well, I completelly forgot, definetly use the ones you suggested. as long as Digikey sell them, or something with the same pin spacing.

Well spotted on the missing clock/osc. I'm working on that now. There will be a master board that the 3 controllers connect to for signal, clock and power.

I found a driver for unipolar motors that used the l297 and the designer came up with a separate clock that was adjustable to help reduce the frying noise (see attached, not finnished tho.) I believe the noise is a result of the chopper cuircuit and clock freq. so by changing the freq you can make it less audible.

Thanks again.for the continuing support, I realise this is going on a bit now