Thanks for the explanation Bart. Your math makes sense.
I think I understand the problem without floating output. The input common to the DC/DC converter is -24v compared to the common in the coming in from the ILDA connector, so there would be a relative difference between the output common of the converter and the ILDA connector. Not sure I understand the solution though. Is floating output a feature of a DC/DC converter? How does it know where to float to?
The datasheet for the Murata 811-2202-ND that Thomas pointed out above says this:
Floating Outputs
Since these are isolated DC/DC converters, their outputs are “floating” with
respect to their input. Designers will normally use the –Output as the ground/
return of the load circuit. You can however, use the +Output as ground/return to
effectively reverse the output polarity.
Does this mean it will just work to make the common from the DC/DC converter match that of the rest of the system?
Originally Posted by
-bart-
Keep in mind that if you choose to supply your DC converter with 48V(2x24v) it should have a floating output.
If not, the common of your galvodriver and the common of your laserdriver(s) will have a voltage differential of 24V.
This will cause a problem, as you will be driving both drivers with one ilda port.
My first projector didn't have any grounding issues but... i had 3 separate power supplies in the projector, 1 for -24v/+24, 1 for 12v, and 1 for 5v. This was the brute force approach I guess. I like the idea of having only 2.
Thanks,
Mike