Hi Colin,

Not that I'm aware of.  Most drives already optically isolate the step/dir inputs so extra opto isolation is not usually necessary.

Winford.com makes basic breakout boards for cables.  For example:
http://www.winford.com/products/brk2x13.php

Regards
TK


On 2016-03-03 10:28, Colin Fera colin.fera@... [DynoMotion] wrote:
 > Is there an easily adaptable to the kflop breakout board that could be
> used break out the step/direction pins from the kflop preferably with
> some kind of isolation?
> 
>  Thanks,
>  Colin
>  Sent from my iPhone 
 

 

Hey Tom,

The drives do have opto's,  there is some issue with noise at times the drive will step randomly when its otherwise idle but enabled.   Also it will lose or gain steps sometimes.  The output was configured as open collector. 

I changed the output to LVTTL and connected the anode to 3.3v instead of 5v and tested for 20 or 30 minutes and didn't see these issues at all. 

The drive manufacture recommends 5v+or-10% but the drive seems to work much better with LVTTL outputs. I was thinking maybe if the drive steps on the rising edge and at a fairly low voltage then there isn't much headroom on top of the 

What would you advise as the long term solution.  Perhaps a level shifter?

If so would this work: http://cdn.sparkfun.com/datasheets/BreakoutBoards/txb0104.pdf

Thanks,

Colin

On Thu, Mar 3, 2016 at 12:36 PM, tk@... [DynoMotion] <DynoMotion@yahoogroups.com> wrote:

 

Hi Colin,

Not that I'm aware of.  Most drives already optically isolate the step/dir inputs so extra opto isolation is not usually necessary.

Winford.com makes basic breakout boards for cables.  For example:
http://www.winford.com/products/brk2x13.php

Regards
TK



On 2016-03-03 10:28, Colin Fera colin.fera@... [DynoMotion] wrote:
> Is there an easily adaptable to the kflop breakout board that could be
> used break out the step/direction pins from the kflop preferably with
> some kind of isolation?
> 
>  Thanks,
>  Colin
>  Sent from my iPhone 

 

Hi Tom,

The drives are these: http://www.dmm-tech.com/Dyn4_main.html

Page 30-32 of the manual provided timing diagrams and lists voltage as 5v +/-10%, max freq as 500khz, minimum pulse width 800us and I think the direction setup is 5us if I am reading the timing diagram right.

Maybe some isolators that would also provide level translation.  http://www.ti.com/lit/ds/symlink/iso7640fm.pdf

The drives have 5v supplies built in which could be connected to the output side of the isolator.

Thanks,

Colin

On Sun, Mar 6, 2016 at 1:33 PM, Tom Kerekes tk@... [DynoMotion] <DynoMotion@yahoogroups.com> wrote:

 

Hi Colin,

What kind of drives do you have?  Do you have the voltage and timing specifications for them?

Open collector mode should apply the full +5V without issue when sinking low, but when floating high (off) the opto may not be held in the off state.  The output is clamped from floating higher than ~3.8V which still applies ~ 1.2V to the opto.  Most inputs need significantly more than this to turn on.

I don't think your chip would work because it only has very weak continuous drive capability due to the automatic direction sensing technique.  In your case you know the direction so that isn't really necessary.

Maybe this if 8ma is enough to drive your optos.
http://www.ti.com/lit/ds/symlink/sn74ahct541.pdf

Regards
TK

On 3/5/2016 7:31 PM, Colin Fera colin.fera@... [DynoMotion] wrote:

 

Hey Tom,

The drives do have opto's,  there is some issue with noise at times the drive will step randomly when its otherwise idle but enabled.   Also it will lose or gain steps sometimes.  The output was configured as open collector. 

I changed the output to LVTTL and connected the anode to 3.3v instead of 5v and tested for 20 or 30 minutes and didn't see these issues at all. 

The drive manufacture recommends 5v+or-10% but the drive seems to work much better with LVTTL outputs. I was thinking maybe if the drive steps on the rising edge and at a fairly low voltage then there isn't much headroom on top of the 

What would you advise as the long term solution.  Perhaps a level shifter?

If so would this work: http://cdn.sparkfun.com/datasheets/BreakoutBoards/txb0104.pdf

Thanks,

Colin

On Thu, Mar 3, 2016 at 12:36 PM, tk@... [DynoMotion] <DynoMotion@yahoogroups.com> wrote:

 

Hi Colin,

Not that I'm aware of.  Most drives already optically isolate the step/dir inputs so extra opto isolation is not usually necessary.

Winford.com makes basic breakout boards for cables.  For example:
http://www.winford.com/products/brk2x13.php

Regards
TK



On 2016-03-03 10:28, Colin Fera colin.fera@... [DynoMotion] wrote:
> Is there an easily adaptable to the kflop breakout board that could be
> used break out the step/direction pins from the kflop preferably with
> some kind of isolation?
> 
>  Thanks,
>  Colin
>  Sent from my iPhone