MUTANT stepper

[student1616]

yes its mutant,
http://img148.imageshack.us/img148/2112/mutanthi9.gif
bcz after looking at these 2 board,i designed this board.

first one is 666's 3-axis simple pic controller
http://www.pminmo.com/3axisPIC/3axisPIC.htm

other one is DAK engineering's PIC16f84 controller.
http://www.dakeng.com/u2.html

i like the 666's simplicity and easiness.but the problem is the PIC.those PIC12c508 are not erasable.u need special programmer to erase the code.
(iam using multipic programmer),so i can't do some experimentation.

the problem with DAK;s circuit is,it uses simple 2n2222's.which can only run small motors.

so i placed the IRF mosfet which can handle lot of current.i'll be using this circuit with 666's chopper circuit.that chopper is really amazing and simple to built.
can u guys post ur views.imean is it ok to use this circuit as it is.or do i need any modifications.
thanks to 666 and DAK
regards

[student1616]

Test Result:1

Programmed the chip 16f84(A) with DAK's original code.(full step mode)
and made a prototype on Breadboard.instead of IRLZ mosfet i had ST's VNP10N06.i thought they will work just fine.
Used MACH3 for testing.
and the result is a HOT PIC.
it burned out after 20mins.(continuous working)

may be 2 things i did wrong.
1.no chopper between the motor and supply.(used 5v for 12v motor).
2.may be PIC output can not drive the VNP10N06 directly.(i need some transistor in between i'll use ULN2803 probably..)

[pminmo]

Proabably the gate capacitance is to much for the PIC.

[student1616]

may be.
what if i place only ULN2803A(500ma per channel so i'll short 2 channels to get 1Amp).it will be enough i guess(no mosfets).bcz the motors iam using are from printers.
http://helitp.dyndns.biz/material/f_.../55spm25d7.jpg
http://helitp.dyndns.biz/material/motores/55spm25d.pdf

one thing i observed during my above test is,while running the stepper using MACH3,the motion was too uneven and vibrating.when i enabled "sherline 1/2 pulse mode"
motion was little smooth.
what shld i do to get good smooth motion.

[reiyuki]

I made a very similar board a while back, except I used a PIC16f628, MOSFETs and a couple resistors/caps for filtering.

Worked well for my very light test project (under 100oz/in)