My first post here, sorry in advance if this question has already been covered. Being a computer scientist, my knowledge about electronics is limited, never had a formal education, a couple of courses when i was a student hardly qualify me as an electronic engineer, so please forgive me again if this question might appear basic (it probably is).
I am currently designing a simple regulated power supply given a center tapped transformer (lets assume a 3.15V-0-3.15V @ 5A secondary) and a SINGLE regulator.
So, having a bridge rectifier + filter caps i assume:
- A somewhere in the region of 4.4415V with respect to GND
- B somewhere in the region of -4.4415V with respect to GND
Now, lets assume the application calls for a) a specific voltage of 6.3V to power vintage tube filaments (DC, regulated, C-D) and b) 5V to power a simple MCU (E-F) from the same transformer winding.
Given the schematic (assume a TO-220 7806 as a regulator on a heatsink, 1n5817 schottky and a 5.1V zener), obviously, it has to be B=D=F, therefore i assume all to be at -4.4415V, right ?
In my case, there is actually no need for a negative voltage, is there a cheap/simple way (without introducing additional silicon, PCB space is an issue :-)) to elevate the negative rail (B/D/F) to GND while still being able to provide 6.3VDC between C and D (other than dropping the center tap) ?
Thank you very much in advance, regards
EDIT: numbers + concrete case description
EDIT: Having considered posted suggestions (thanks to @fraxinus, @Marcus Müller for pointing out that the transformers voltage is too low for a decent regulation), i came up with an update that i hope to suffice for my application (see image).