Different PSU designs advice.
Feb 26, 2006 at 6:58 AM Thread Starter Post #1 of 1


Headphoneus Supremus
May 19, 2004
I've built a DAC which is currently running from my bench supply but obviously it needs some real power supplies built and I was thinking of customising each rail to it's needs.

I need 3.3VL, 3.3V (for a PLL therefore very low noise), 5VA for the DAC, and +/-15VA for the output stage.

I was currently thinking of using just a plain LM317 for the logic devices, a Jung regulator for the output stage. However since the jung design is harder to get running at low voltages I was also considering some other designs.

The TL431 based shunt regulator apparenlty leaves the LM317 option for dead if properly implimented, and has excellent in band SNR. However the graphs I've seen were only for 20-20khz. Since i was thinking this part for the Phase Locked Loop it needs to have low noise at high frequencies too so I was wondering if anyone here has any experience with this circuit?

And can anyone recomend another design for 5VA and 3.3VPLL that has excellent noise specs? This is all low very low current btw. 10mA typically for the PLL and <50mA for the DAC

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