I have two ATX power supplies with +12 rails. However the -12 rails do not have enough current rating for my application.
Thus I would like to combine two supplies in series. One will have the +12 referenced to the GND of the other unit.
This requires isolating the GND of the unit used for the NEGATIVE supply from Chassis ground. This is easy enough, but
I am worried about any ICs that are used... will they have the correct voltage to operate? Things like heatsinks are also grounded. It is just kind of odd.
Someone has done this with other types of SMPS, just not computer supplies. For example, I know it can be done with this unit:
https://www.electro-tech-online.com/custompdfs/2009/08/PBA150F-1.pdf
However I have seen a few pictures of the PCB on that unit and cannot see any ICs except for one TO-220 package, not sure what it is.
anyone have thoughts on this? thanks.