In this application note by ST
On page 6, section III- Measure on mains, it used the equation:
Fc=(Rtotal*C*2*pi)=1.1kHz
But when i calculated the values 6250*2.2e-9*2*pi, i got 8.639e-5. What's wrong?
Another thing, i thought the equation for cutoff frequencies were Fc=1/(2*pi*R*C)?
The document is wrong, on two counts! The equation for Fc in a simple RC circuit is 1/2piRC as you've stated (they left out the 1/ part, or a (-1) exponent). Also, they calculated wrong - it should be 11.6KHz, not 1.1KHz.
"w2aew"
** Not to mention the danger and stupidity of connecting the chassis ground of an Spectrum Analyser to the supply neutral.I note the article was written by two frogs.
Beware - they are really toads.
........ Phil
D**n!
The blind leading the blind.
I wonder how many papers and ANs i have that has such mistakes. Don't they ever check before they publish?
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