Faisal wrote on Sep 13th, 2007, 8:13am:Do I need to use buffers.. or better cables.. what are the possibilites?
Kind Regards,
Fas
Hi Faisal,
You could try out active probes (which usually have much smaller capacitances than the passive ones) and shorten the cables as much as possible.
Buffers are another alternative but might offset to your measurement.
Hi ligthgo,
One option to measure noise is to record at least 100 sweeps of the bandgap voltage signal, 0.01s long each, from the scope. This way you are letting the noise content of 100Hz an above to take effect on the signal, and at the same time taking fairly enough number of samples. You could then capture the datapoints from the scope and process it with matlab, by using one of the PSD estimators it provides. After such calculation you will be able to see the profile of the noise signal and its total power by simply integrating it.
Hope this helps
Tosei