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TerraMex · 08-17-2003, 08:58 PM

> Does that make sense? Reversing flow would cause the
> negative voltage, right?

I see your point, but power supply units were not built to be run on reverse. IMO, it wouldnt work... and if it did, not for long.

That's why there's inverting circuits. If it was that simple, we just connect things on reverse and save alot of electronics.

Anyway , i just realized (damnit, it took alot of time), you have a -12v rail on the PSU. You can actually use that, if the current draw isnt very high ; mine is rated for 0.8 A, which is pretty good.

And as far as i know (no certains) the -12v is just a reference voltage rail.

And you can also use a small DC-DC converter and pump the -12v to -20v.

>The resistor symbol with "VR" next to it is unfamiliar, as is the
>symbology used around "Tr". If someone could explain this I
>would be ever in their debt.

As far as i can relate VR equals Variable Resistance.

And it makes sense. The middle resistance has the "->" which means it doesnt have a fixed value, thus can be ajusted.

Edit : misread, the Tr refers to something else.

http://www.chipdocs.com/pndecoder/da...S/2SA1202.html

PS: The "Module" there supplies positive and negative voltages, the circuit attached serves as power regulator, imo.

08-17-2003, 08:58 PM	#8
TerraMex Cooling Savant Join Date: Nov 2002 Location: Portugal, Europe Posts: 870	> Does that make sense? Reversing flow would cause the > negative voltage, right? I see your point, but power supply units were not built to be run on reverse. IMO, it wouldnt work... and if it did, not for long. That's why there's inverting circuits. If it was that simple, we just connect things on reverse and save alot of electronics. Anyway , i just realized (damnit, it took alot of time), you have a -12v rail on the PSU. You can actually use that, if the current draw isnt very high ; mine is rated for 0.8 A, which is pretty good. And as far as i know (no certains) the -12v is just a reference voltage rail. And you can also use a small DC-DC converter and pump the -12v to -20v. >The resistor symbol with "VR" next to it is unfamiliar, as is the >symbology used around "Tr". If someone could explain this I >would be ever in their debt. As far as i can relate VR equals Variable Resistance. And it makes sense. The middle resistance has the "->" which means it doesnt have a fixed value, thus can be ajusted. Edit : misread, the Tr refers to something else. http://www.chipdocs.com/pndecoder/da...S/2SA1202.html PS: The "Module" there supplies positive and negative voltages, the circuit attached serves as power regulator, imo. __________________ "we need more cowbell." Last edited by TerraMex; 08-17-2003 at 09:05 PM.