Questions on Noise Budgeting for Electronics

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The discussion centers on noise budgeting in electronics, specifically addressing 1/f flicker noise, thermal drift noise, and capacitor noise. Concerns are raised about the impact of flicker noise on resistance measurements, particularly regarding stability over time and the accuracy of average voltage readings. The user seeks clarification on how to calculate expected errors due to flicker noise and the appropriate bandwidth for measurements taken at specific intervals. Additionally, questions are posed about the temperature changes in SMD resistors and op-amps due to air movement in a lab environment. The conversation also touches on the comparison of noise characteristics between high-pass and low-pass filters.
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A few questions about noise. I am doing a noise budget and I am not sure if everything is correct...


1/f flicker noise


Resistors show this noise. Horowitz specifies microvolt per decade frequency per applied volt.
This would give me a false reading on a four point measurement, at least that is how I understand it, because the applied voltage won't really flicker will it. Is this noise real noise in the resistivity? Does it mean the resistance is not very stable over a year? So when I measure the resistance with an AC Voltage of 100KHz will I see a resistance drift in time caused by flicker noise?

Let's say I measure some voltage, and the measurement is such, that it produces the average value over one second. Can I calculate the expected error due to flicker noise? Can I only specify the expected drift till the next measurement?

If I take 1 measurement every 90 seconds for 5 hours. Am I correct in specifying the bandwidth to be the frequencies between 1/(3 minutes) (sampling theorem) upper and 1/(300 minutes) lower frequency, so two decades for the purpose of flicker noise?


Thermal drift noise

How much and how fast does the temperature of a smd resistor or op amp typically change in a metal box due to air movement in a lab? (external power supply, low power chips) What is the frequency spectrum?


Capacitor noise


Is the noise on a high pass the same as on a corresponding low pass?
 
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