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Digital Lowpass: A filter by any other name is still a filter

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PixchipsAtTi
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re: Digital Lowpass: A filter by any other name is still a filter
PixchipsAtTi   3/5/2012 5:14:04 AM
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Aha! I see what you mean, but we were talking about the impulse response of an RC lowpass filter not the impedance of the RC network. An impulse provides an infinitely thin infinitely high pulse to the R that causes an infinite current pulse that charges the C instantly to a finite value (math folks will have to forgive me here) and then it disappears. So most of the response is with zero input and a charge on the cap. The charge decays exponentially. The digital ckt gets its impulse as a '1' for one clock cycle, and then decays similarly. Hope that helps!

JohnJuan
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re: Digital Lowpass: A filter by any other name is still a filter
JohnJuan   4/28/2010 2:37:05 PM
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I'm not sure that I'm missing something here, but the impulse response in figures 2 and 3 is that of an inductorn, not a capacitor (with we are to remain consistent with ELI the ICEman). Love the series, thank you!

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