On Mon, 2011-12-12 at 20:03 +0100, Electron wrote:
> Hello,
> I have to get the *exact* timing (30ns resolution) of some low frequency =
(<250Hz) pulses
> via an input capture module, however I'd like to filter the signal coming=
 in, as it will
> contain a lot of high frequency noise, but filtering via a capacitor intr=
oduces a phase
> delay, which I can't even compensate (by frequency) as the phase delay ch=
anges with input
> signal amplitude.
>=20
> What is the way You'd approach this problem? I thought about using a zene=
r to clip the
> signal and thus work on a known amplitude, but I suspect it will introduc=
e errors too.
>=20
> On the software side, I could make sure that the input stays high for eno=
ugh time, but
> it's pretty overkill, and I'd like to keep it as last option. If it could=
 be done [EE]
> then it would be better!

Filter in software?

TTYL

--=20
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