Re: SPICEing The Inductance of a Trace Over a Ground Plane?

On Tue, 18 Sep 2007 08:51:18 -0700, John Larkin
<jjlarkin@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

On Mon, 17 Sep 2007 21:34:35 -0700, "Joel Kolstad"
<JKolstad71HatesSpam@xxxxxxxxx> wrote:

"D from BC" <myrealaddress@xxxxxxxxx> wrote in message
news:0daue3l50e11g711v8qpaui0qag3u1a637@xxxxxxxxxx
then using this strip model (transmission line model)
with a pulse gen and load...

pulse > ---- L ------>Hi Z load (CMOS input)
| |
C/2 C/2
| |
Gnd Gnd

..It looks like this can have severe ringing...

Yes, but this is due to your pulse having a very fast rise time. If you
want to use pulses, for a given rise time make the delay through each L-C
section around, say, 1/10th of the rise time and then you'll give a
reasonable facsimile of the pulse at the far end.

Isn't this also called a pie filter..?

Yes it is (albeit spelling "Pi" as in 3.14..., not "pie" as in "tasty treat
that's calorically dense").

I just made a peach-blackberry pie, with the last blackberries of the
season. Yum. It is round.


John

640mm or so circumference?


Best regards,
Spehro Pefhany
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