Any comments on the attached schematic? It seems to me that this design would better reject common mode noise in the AC, but I don't know enough to be sure. I don't remember ever seeing such a scheme shown in a schematic, but I don't know if that means it's pointless or if that as parts count go up, a designer will forgo a 3 terminal regulator in favour of discrete components.
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I think there's no need, the transformer galvanic isolation provides the rejection of common-mode noise from the mains. All you are doing there is doubling the supply impedance and creating twice as much heat, real estate and cost.
Common mode noise should be pretty much eliminated by the transformer. For non-CM noise, I don't believe this circuit buys you anything either.
Is there some issue you are trying to solve here?
-tINY
It's a split power supply without using the middle rail as ground.
Maybe it can be used to get a higher voltage with lower voltage regulators?
Maybe it can be used to get a higher voltage with lower voltage regulators?
tINY said:
Is there some issue you are trying to solve here?
Not an issue, no. I am planning to build a phono preamp with poor PSRR and want the best performance regulator I can get without going to a discrete design.
Forget using 78xx or 79xx regs then. Check out the low noise applications on the LM317 datasheet.
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