Maker Pro
Maker Pro

hard problem needing a genuse man familiar with 4phase stepping motor ics

Y

yar

Jan 1, 1970
0
hi
I have a problem with stk6713bmk3 I cant not find it &I try to
making its equivalent circuit .it is an unipolar fixed chopper-type
4-phase stepping motor drive hybrid ic which uses a mosfet power
device I getting the data sheet from www.datasheetarchive.com it has
this components list ( 4 mosfet transistor +2positive negative
opamp(is1458ok?)+4nor gate (what ic suggested)+8resistance I have not
it's value +2caps I havenot it's value too)
if this way is wrong what I can do ? is ther is an ic I can used it
as a replecement

I find the l297 is 4-phase stepping motor controller with adifferent
circuits diagram
 
J

John Popelish

Jan 1, 1970
0
yar said:
hi
I have a problem with stk6713bmk3 I cant not find it &I try to
making its equivalent circuit .it is an unipolar fixed chopper-type
4-phase stepping motor drive hybrid ic which uses a mosfet power
device I getting the data sheet from www.datasheetarchive.com it has
this components list ( 4 mosfet transistor +2positive negative
opamp(is1458ok?)+4nor gate (what ic suggested)+8resistance I have not
it's value +2caps I havenot it's value too)
if this way is wrong what I can do ? is ther is an ic I can used it
as a replecement

I find the l297 is 4-phase stepping motor controller with adifferent
circuits diagram

According to the data sheet, R7 and R8 (the current sense resistors
are .33 ohm.

R5 and 6 are not very critical, just over current protection for the
clamp diodes and to allow some positive feedback during switching via
R3,4, C1,2. I think 1k ohms should be a fair guess.

R1 and 2 are logic pull ups for the output of the comparators.
Something on the order of 4.7k should work with most comparators. If
you use CMOS comparators with logic outputs instead of bipolar
comparators with open collector outputs, they are not needed at all.

From the Iol, Ioh ratio, you can guess that the positive feedback is
about 10% to 15% of the 1.1 amp average current, so that would make
R3,4 about 120k.

C1,2 are there to boost the positive feedback for a small part of the
normal on time to cover transients in the switching. I think about a
microsecond or two should work. That makes them about 47 to 100 pf.

The nor gates need to have quite a bit of output current capability to
drove the mosfets quickly. The HC cmos series might work.
 
Top