Hello Everyone,
I need some help starting out with CNC. I am going to build a CNC router
type machine to route pcbs. I need some help with the circuits.
I have 3-60oz in stepper motors I got from HobbyCNC. They are marked
STH-55D203-02 1.8 deg/step, 5.1V 1A. I believe they are unipolar from the
docs and they have 6 leads coming from them. This is my first adventure
with controlling stepper motors. I have another project for CNC when I get
finished with this one. My mother (I am 34 as of Sunday) wants one of
those embroidery sewing machines that cost $3000+. She want's to do some
sewing designs and monograms on clothes. If I get my CNC router/driller
working, I am going to attempt to build her one with the other group of 3
unipolar stepper motors I have.
I went looking for ICs to control all of the stepper motors I have. I have
a total of 6 motors, 3 being of one make and spec, and the other 3 being of
another make and spec. Each group of 3 motors is the same spec, so I do
not have to worry about trying to control motors of different
characteristics. I found the UCN5804B to be a good chip, but it will not
meet the power specs of both stepper motor group I have. They have
different current ratings. One group is 1A, the other 1.44A. So, I will
need some transistors that can interface with the 5804B so that no matter
which motor group I am using, the circuit will power them.
I found the TIP 120 to be able to put out up to 3A, which is more than
enough. Page 5 of this doc:
http://www.alltronics.com/download/5804.pdf shows the circuit I would like to build. I know that I will need the
diodes as circuit protectors. Can anyone show me how to hook up the Tip's.
I had lots of theory 12 yrs ago in college, but could not graduate do to
not being able to pass calculus. They blocked me from taking my Senior
level classes. So I wasted a lot of money!
I did an extensive search on the net and came across several chips, but
would still need the extra transistors to power the more current hungry
motor. Also, these chips were more expensive. It is not that I am being
cheep, I could purchase a board which many on this group seem to sell, it
is just that I wish to learn more about electronics.
I am looking to purchase the chips this week, so I anyone could help me
out, I would appreciate it.
Thanks,
Brian G.