Is it possible to design a fixed AC input and multiple voltage values +/- DC outputs?

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Vintage Yamaha

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#1
Is it possible to design a fixed AC input and multiple voltage values +/- DC outputs?
Transformer primary 120v
Transformer secondary is 58 - 0 - 58
Need:
+48 -48,
+12.5,
+17 - 17

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Also needs to include this protection function on the new power supply PCB

FYI: PL is the front panel LED

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#6
58V AC rectified gives around 81V DC. So with your nedded 48V DC @1A you have to burn 33W (I'm just looking at one side of the supply valtage here).
Maybe you can consider using a different transformer? 34-35V AC would be good for 48V DC without a regulator.
 
#8
No need for denoiser, just plain lm317/337 combo is good enough for opamp supply.

Your transformer can supply +/- 48v dc with the two red wires and the black wire should then be the middle connection( 2 x 35.1V .

With the blue wires you can make the 12.5v supply(just one lm317).

Opamp supply can be generated from +/- 48v with lm317hv/337hv, but is far from ideal. Better to take separate 2 * 15v transformer.
 
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#9
The attached schematics are the different sections of an integrated amplifier:
Power Amplifier x 2
Pre Amplifier x 1
Relay Controller for Line Input signals to the preamp x 1
Internal Cooling Fan x 1
Speaker Protection x 1

I don't want to build 5 different power supplies. My goal is to have one common power supply with different DCV requirements

12. The existing regulated power supply provides voltage for the PreAmp, Protection, Selectors (relays), and the front end of the Main Amp pcb’s. The internal fan has a seperate power supply, I would like to combine that into the single power supply PCB. I would like to see if all these could be incorporated into one PCB. The caps may need to be placed on a separate PCB due to space limitations. The Yellow wires on the transformer are providing the voltage for the existing regulated power supply. That existing power supply will be replaced with this new design.

My goal is to find an expert that can create the design in LtSpice.
 
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#10
Well, one supply... a proper one has trafo windings that supports the needs - yours really don't.. so problems... you need to drop a lot of voltage... that cumbersome... and a +/- supply... center taps, to serial or dedicated negative regulator... lotsa things to consider.. no easy shortcuts...

//
 
#12
Why quite? Your preamp has opa1656 with -120db PSRR. Using lm317/337hv ads -65db to that.
-185db is very quite.

For the power amp section you can use capacitor multiplexer, you lose 4v on every rail. Normally just rectifier en big caps are enough for best dynamics.
 
#13
Monstercore said:
Why quite? Your preamp has opa1656 with -120db PSRR. Using lm317/337hv ads -65db to that.
-185db is very quite.

For the power amp section you can use capacitor multiplexer, you lose 4v on every rail. Normally just rectifier en big caps are enough for best dynamics.
Click to expand...
The Main Power Amp uses regulated +-50vdc and unregulated +-50vdc. I am inquiring about the regulated power supply.

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UNREGULATED POWER SUPPLY
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