I have 4 IM483 stepper motor drivers, and they have a 5V opto supply =20
input pin.  There is a separate supply for the rest of the board.  It =20
looks like we may have accidentally hit the opto supply with a much =20
higher voltage (either 12V or 34V) for a split second, and all drivers =20
are dead now (the 5V pins are tied together).  Motors energize/hold, =20
but won't respond to step pulses.

Looks like we may have fried the input opto isolators, and I'm hoping =20
that's all.  The allegedly-fried optoisolators state "630 803" (two of =20
them in lower left of pic).  A tech at IMS said they were probably =20
HCPL0630 with 803 being a date code.  Datasheet =3D
http://download.siliconexpert.com/pdfs/2009/2/1/8/39/40/avago_/manual/av02-=
0940en%5B1%5D.pdf

Anyone know anything about these drivers or opto chips, and perhaps =20
can recommend some tests to verify if that's really the issue?  And =20
could there be something else fried?  I have one other new working =20
unit here (PCB is a bit different, but optoisolators are the same), so =20
I can compare signals between the two.  The board seems to be 4-layer, =20
so it's not easy to visually trace signals.

Drivers are here...
http://www.veisystems.com/nose/temp/IM483-Top-View-01.jpg
http://www.veisystems.com/nose/images/2010_0815-RW-Stepper-Drivers-01.jpg

For the curious, manual is here...
http://www.imshome.com/downloads/manuals/im483.pdf

Cheers,
-Neil.




--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.