in lieu of a breakout board

[fly_champ]

did not see a previous discussion on this topic.
I am in the process of building my first small cnc.

Is it possible to increase the current output of a unipolar chopper driver circuit by using the original outputs attached to the gate of a large capacity FET in order to slave more than one motor to the same axis, instead of using a breakout board?
By my reasoning, all you would need is four FET's and maybe resistors on the FET inputs. The idea is fet's are cheap as dirt, and breakout boards aren't.

[pminmo]

http://pminmo.com/db25/basicBOB.htm Free with a little effort. :-)

Phil

[H500]

Fly: it's not impossible, but it's much more involved than just connecting the gates to the outputs. For example:
1. On all drivers I seen, the outputs go low to turn the coil on.
2. What about current limiting?
3. The out voltages are probably too high for the gates

[fly_champ]

Thank you for the link pminmo.

I am trying to find an easy and cheap way to make a four axis cnc hot wire
and I would like to make it convertible to a three axis router by combining the motors on two axis and adding a y axis in place of the wire.

this is new territory for me, as I am used to using large scale servo drives, etc in the
machines we design where I work. I am building the controls because I didn't like the prices of commercial stepper drivers.

How many axis can be driven from one parallel port, if the total number is five or more, I will just make a driver board for the number of motors I want to use, and slave them via software or something.

thanks Jon