about filters..

[sirvo]

I'm developing a onboard computer for my chev and i would like to acquire some analog signals like temperature. I know it ranges from 0 to 5V but i think that there is some noise.... Does anybody know any low-pass filter so that i can use to acquire a good signal? A think i should use some amp-ops with r and c to filter .... but i dont know...

sorry my english..

thanks in advance...

Sylvio

[skimask]

I'm developing a onboard computer for my chev and i would like to acquire some analog signals like temperature. I know it ranges from 0 to 5V but i think that there is some noise.... Does anybody know any low-pass filter so that i can use to acquire a good signal? A think i should use some amp-ops with r and c to filter .... but i dont know...

sorry my english..

thanks in advance...

Sylvio

And we're supposed to guess your frequency range?
Put a .1uf across the signal to ground.
Do the filtering/averaging in software.

[mister_e]

f=1/(2*PI*R*C)

rc filter would work, OP-AMP have it's advantages as well. Both will use the same eternal formula.

http://en.wikipedia.org/wiki/Low-pass_filter
http://www.discovercircuits.com/PDF-FILES/LowPassFilt1.pdf

Easier than calculate the ultimate enclosure for a x
Subwoofer in a dipole setup.