AlienCircuits
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I am using a voltage reference part, and I would like to make this voltage as noiseless and temperature stable as possible. I guess my questions are general, but, if it helps, the specific reference part that I've chosen is LM285LPR-2-5 https://www.mouser.com/ds/2/405/slvs023j-206162.pdf . I am biasing the source like the datasheet suggests, and then the voltage is applied to the high impedance input of an opamp.
I am considering a few basic ways to try to fortify this reference to make it as stable and noiseless as possible. I am simple-mindedly thinking that I could put bypass caps on the input and output ends of the part, and then I started thinking that maybe this could actually make the signal worse because I've just added more components that can vary with temperature or other variables. I also know that ceramics can introduce noise with their piezoelectric effect and so I would avoid those.
I was also thinking of providing the voltage to the opamp through a via directly at its pin and then a bypass cap on the pin, so that the via's parasitic inductance could help choke out some noise. I know that idea sounds a little far fetched and the via might be doing nothing depending on the frequency of the noise.
So now, I am not sure if I should proceed to add caps, or just leave it by itself. Does anyone have any advice for me please? If I do put in caps, what is the best cheap capacitor technology for this application (Its not worth it to spend $2 per a cap for me).
I am considering a few basic ways to try to fortify this reference to make it as stable and noiseless as possible. I am simple-mindedly thinking that I could put bypass caps on the input and output ends of the part, and then I started thinking that maybe this could actually make the signal worse because I've just added more components that can vary with temperature or other variables. I also know that ceramics can introduce noise with their piezoelectric effect and so I would avoid those.
I was also thinking of providing the voltage to the opamp through a via directly at its pin and then a bypass cap on the pin, so that the via's parasitic inductance could help choke out some noise. I know that idea sounds a little far fetched and the via might be doing nothing depending on the frequency of the noise.
So now, I am not sure if I should proceed to add caps, or just leave it by itself. Does anyone have any advice for me please? If I do put in caps, what is the best cheap capacitor technology for this application (Its not worth it to spend $2 per a cap for me).
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