For some nano-physics related measurements, a very clean low-noise bias current is required. People mostly use a battery powered isolated voltage source along with a big resistance similar to this.

  1. Is there anyway, alternatively I can have a clean source using a regular voltage source, let's say a Keithley DC power supply, and an off-the shelf filter to clean it up?

  2. Any recommendation for the filter?

Appreciate your responses.

Added notes:

I would like the noise to be in the order of 10 μVrms (1kHz bandwidth), similar to the device above. By recommendation: I mean what to search for. Is there any technical term for these types of filters.


closed as too broad by JRE, RoyC, JYelton, Finbarr, Lior Bilia May 16 at 19:37

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    \$\begingroup\$ For the kind of noise control that you're talking about, you're not going to get an answer from the internet. You're going to have to try some experiments and see what works in your environment (interference sources) and for your application (how low does the noise need to be? In what frequency bands? etc) \$\endgroup\$ – The Photon May 9 at 18:36
  • \$\begingroup\$ An interesting question, but recommendations for things to buy are off topic here. \$\endgroup\$ – JRE May 9 at 18:58
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    \$\begingroup\$ You should say how long the voltage source needs to operate, what the bias current range is (should I assume you mean a current source from the context I'm reading -- sounds like it -- but you should say if that's so), what noise specs you have for "low-noise" and "clean." Etc. You can make a very "clean" voltage reference in a chem lab. But it works well only for so long of a time. \$\endgroup\$ – jonk May 9 at 21:35
  • \$\begingroup\$ Thank you all for your answers: @ThePhoton in the order of 10 μVrms (1kHz bandwidth). . \$\endgroup\$ – user101464 May 10 at 13:54
  • \$\begingroup\$ Thank you @JRE: I mean what to search for. Is there any technical term for these types of filters \$\endgroup\$ – user101464 May 10 at 13:54