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Small and quite +/-8v power supply/regulator
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CuriousAbe:
So I've come pretty far in my summer project to clone a certain old analogue drum machine and now it's time for the power supply.

The original unit is powered by a good ol transformer, 2x 2200uf caps, 2x 10uf caps, a full bridge rectifier and a 7808 and 7908 voltage regulators, needless to say it's pretty noisy.

For various reasons I have decided not to supply the kit it with a linear psu and a transformer involving mains wiring.

So I'm looking for a reasonably small and quite +/- 8v supply/regulator design, requirements:

*Must fit on a board that is max 145x45mm (50mm height)
*+/- 8v output
*Around 200-300ma output
*No mains wiring, preferably input should be with a ac/dc power adapter (ac/ac works too)
*Switching design is fine by me as long as it's reasonably quite
*Preferably all through hole components
ogden:
Why don't you like original power solution of linear supplies? Don't spoil your *analog* build with switching supply :)

You can't avoid mains because wall plugs or brick supplies, usually are single output. You could use power module, but it requires AC wiring & AC fuse holder: AC->DC two output +/-12VDC *module* like Raccom RAC06-12DC. Obviously with two linear regulators behind it. Don't use prehistoric 7808 and 7908. Use LT3045 and LT3094 instead. Pricey but low noise as you wished, will not regret that choice.
iMo:
LM317/337 are cheap and quiet too (with a capacitor in the divider).
CuriousAbe:

--- Quote from: ogden on July 24, 2019, 10:02:10 pm ---Why don't you like original power solution of linear supplies? Don't spoil your *analog* build with switching supply :)

You can't avoid mains because wall plugs or brick supplies, usually are single output. You could use power module, but it requires AC wiring & AC fuse holder: AC->DC two output +/-12VDC *module* like Raccom RAC06-12DC. Obviously with two linear regulators behind it. Don't use prehistoric 7808 and 7908. Use LT3045 and LT3094 instead. Pricey but low noise as you wished, will not regret that choice.

--- End quote ---

Well I will be selling the clone as a kit (pcb's+case) and I don't want people who are not comfortable handling mains wiring doing so, and I know people who are not comfortable with mains will be buying this kit.

Yea I was thinking on the small module route, however there seems to be a gazillion different small ac/dc modules to chose from :P  Will keep the LT3045 and LT3094 in mind!

Another idea is to make something like this, maybe I could redesign it to use the LT3045 and LT3094 regulators instead.
http://musicfromouterspace.com/analogsynth_new/WALLWARTSUPPLY/WALLWARTSUPPLY.php


Input is a 12VAC power adapter (problem here is that these are not that usual to come by for cheap in europe).
ogden:

--- Quote from: CuriousAbe on July 24, 2019, 10:28:41 pm ---Will keep the LT3045 and LT3094 in mind!

--- End quote ---

Definitely overkill for DIY kits. Better use mentioned LM317/337.


--- Quote ---Input is a 12VAC power adapter (problem here is that these are not that usual to come by for cheap in europe).

--- End quote ---

Why your specified current is so high, 200mA? Anyways for 12VDC power adapter (wall-wart) there's solution for negative rail: isolated DC-DC 12V->12V converter like Murata NXE2S1212MC-R13

Through hole: SPU01M-12 from MeanWell, but it's 80mA only, very noisy on both sides, input & output. Make sure to use LDO's with good PSRR.
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