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I'm planning to use TI's DCV010505DP DC-DC converter to generate a low noise, +/- 5V dual rail supply with a ground node. I plan to use a cheap wall-adapter power supply to power the DC-DC converter. At the outputs of the converter, I want to ensure that the voltage remains fixed and also perform some filtering, so I've added an LM317 and LM337 with input and output filtering capacitors as well as reverse current protection via diodes. I'm going to be sensing sensitive analog signals using an 18-bit ADC, so that will be quite important.

Is this scheme feasible for generating a low noise power supply? Specifically,

  • Should I add anything to the input side of the DC-DC converter to reduce noise?
  • Are there any "tricks" to generating low noise supply voltages in terms of convenient chips for wall-plug to board low noise interfaces?
  • Any tips would be greatly appreciated!

My current schematic is shown below.

Schematic.

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    \$\begingroup\$ You may want to give TI AN2162 a read. \$\endgroup\$
    – Matt Young
    Sep 25, 2016 at 14:45
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    \$\begingroup\$ How much current do you need on these split rails? Also, what voltage is the wall adapter putting out? \$\endgroup\$ Sep 25, 2016 at 15:00
  • \$\begingroup\$ 5V wall adapter and only ~100 mA of current is required. \$\endgroup\$
    – nick_name
    Sep 25, 2016 at 15:16
  • \$\begingroup\$ What noise spec are you targetting (don't say as low as possible or words to that effect). \$\endgroup\$
    – Andy aka
    Sep 25, 2016 at 17:48
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    \$\begingroup\$ You want to look at the specs of LM317 and LM337 and compare them to some more modern regulators. In particular, look at line regulator, output noise voltage. \$\endgroup\$
    – rioraxe
    Sep 25, 2016 at 21:57

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