[IBIS-Users] How Ramp data is processed ?

Hello IBIS Users

When only ramp data exist in the model.
As far as I understand the ramp rate is used to calculate the two weight
functions (one of the pull down and one for the pull up) that describe
this transition (high to low or low to high).

 From Ramp we got the V(t) that describe the transition (linear curve).
The resistor load is also known R_load.
We also got the I(V) curves for pullup and pulldown (I will mark this
function as I(V)pu and I(V)pd).
I will mark the weight function as W(t)pu for pullup and W(t)pd.
Then we can write this equation for the transition:

V(t) = R_load* (I(V)pu * W(t)pu - I(V)pd * W(t)pd)

In order to get the W(t)pu and W(t)pd we need one more equation.
What I am missing here ?
Can anyone point me to a relevant paper on this subject ?

-- 
Regards
Itzik Peleg 
Board Technology Group
Marvell Semiconductor Israel Ltd
6 Ha'mada St. Industrial Area
P.O.Box 692 Yokneam  20692  ISRAEL
Email - itzik.peleg@il.marvell.com
Tel   - +972 4  9091192  
Cell  - +972 54 4452482
Fax   - +972 4  9091501
WWW Page: http://www.marvell.com
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