Timeline for Noise and what does V/√Hz actually mean?
Current License: CC BY-SA 3.0
11 events
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| Apr 24, 2014 at 18:48 | comment | added | endolith | note that if your spectrum measures W/octave instead of W/Hz, those two graphs will be tilted counterclockwise, and pink noise plot will be flat. | |
| Jun 18, 2012 at 7:03 | vote | accept | jippie | ||
| Jun 18, 2012 at 5:18 | comment | added | stevenvh | @jippie - Yes, flicker noise is pink. The T is obviously the chip's temperature, but R isn't about the input impedance, which in fact may be very high, like 10\$^{12}\$ \$\Omega\$. It's about resistances in the device, where the free movement of charge carriers cause the noise. That's required, otherwise an infinite resistance would cause an infinite noise and that doesn't happen. Otherwise that 10\$^{12}\$ \$\Omega\$ input impedance would cause no less than 18 mV RMS noise over the audio bandwidth. | |
| Jun 17, 2012 at 18:04 | comment | added | jippie | 'flicker noise' = 'pink noise'? You base your explanation on thermal noise in a resistor, can I compare R and T with input impedance of the opamp and the chip's temperature? (my feeling says 'no', but I don't know why). | |
| May 20, 2012 at 17:27 | history | edited | stevenvh | CC BY-SA 3.0 |
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| May 20, 2012 at 17:26 | comment | added | stevenvh | @Telaclavo - I know! :-) But I sometimes make the mistake because I also know (some people make errors against that) that the abbreviation for a unit derived from a person's name is indeed with a capital letter. Hence the confusion. I'll fix it. | |
| May 20, 2012 at 12:07 | comment | added | Telaclavo | It is "volts per square root hertz", "joules", "kelvin" (all in lowercase, except if they start a sentence) and "3 dB/octave" (with a space between the numeric value and unit symbol). See Tables 1 and 3 in physics.nist.gov/cuu/Units/units.html , and #5 ("meters per second" in example) and #15 in physics.nist.gov/cuu/Units/checklist.html | |
| May 20, 2012 at 9:59 | history | edited | stevenvh | CC BY-SA 3.0 |
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| May 20, 2012 at 9:43 | history | edited | stevenvh | CC BY-SA 3.0 |
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| May 20, 2012 at 9:35 | history | edited | stevenvh | CC BY-SA 3.0 |
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| May 20, 2012 at 9:29 | history | answered | stevenvh | CC BY-SA 3.0 |