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Oli Glaser gave a fantastic answer to a question regarding termination resistors: SDRAM Termination Resistors: Are They Needed?

I am trying to replicate his wCalc and SPICE simulation calculations for learning purposes.

I've got about everything figured out except how exactly he came to his wCalc results.

Here is a screenshot at my failed attempt of coming to the same result as Oli did using wCalc.

Oli gets:

Zo = 177.6Ω
L = 642.9 pH/mm
C = 0.0465 pF/mm
R = 34.46 mΩ/mm
Delay = 530.4 ps

I get:

Zo = 117.6Ω (considerably off)
L = 642.8 pH/mm (only 0.1 ph/mm off)
C = 0.0465 pF/mm (same)
R = 9.072 mΩ/mm (considerably off) 
Delay = 530.3 ps (only 0.1 ps off)

Since some numbers, L, C, and Delay are equivalent or off by just a fraction, but Zo and R are considerably off, I'm a bit perplexed.

Oli Glaser gave a fantastic answer to a question regarding termination resistors: SDRAM Termination Resistors: Are They Needed?

I am trying to replicate his wCalc and SPICE simulation calculations for learning purposes.

I've got about everything figured out except how exactly he came to his wCalc results.

Here is a screenshot at my failed attempt of coming to the same result as Oli did using wCalc.

Oli gets:

Zo = 177.6Ω
L = 642.9 pH/mm
C = 0.0465 pF/mm
R = 34.46 mΩ/mm
Delay = 530.4 ps

I get:

Zo = 117.6Ω (considerably off)
L = 642.8 pH/mm (only 0.1 ph/mm off)
C = 0.0465 pF/mm (same)
R = 9.072 mΩ/mm (considerably off) 
Delay = 530.3 ps (only 0.1 ps off)

Since some numbers, L, C, and Delay are equivalent or off by just a fraction, but Zo and R are considerably off, I'm a bit perplexed.

Oli Glaser gave a fantastic answer to a question regarding termination resistors: SDRAM Termination Resistors: Are They Needed?

I am trying to replicate his wCalc and SPICE simulation calculations for learning purposes.

I've got about everything figured out except how exactly he came to his wCalc results.

Here is a screenshot at my failed attempt of coming to the same result as Oli did using wCalc.

Oli gets:

Zo = 177.6Ω
L = 642.9 pH/mm
C = 0.0465 pF/mm
R = 34.46 mΩ/mm
Delay = 530.4 ps

I get:

Zo = 117.6Ω (considerably off)
L = 642.8 pH/mm (only 0.1 ph/mm off)
C = 0.0465 pF/mm (same)
R = 9.072 mΩ/mm (considerably off) 
Delay = 530.3 ps (only 0.1 ps off)

Since some numbers, L, C, and Delay are equivalent or off by just a fraction, but Zo and R are considerably off, I'm a bit perplexed.

Oli Glaser gave a fantastic answer to a question regarding termination resistors: SDRAM Termination Resistors: Are They Needed?

I am trying to replicate his wCalc and SPICE simulation calculations for learning purposes.

I've got about everything figured out except how exactly he came to his wCalc results.

Here is a screenshot at my failed attempt of coming to the same result as Oli did using wCalc.

Oli gets:

Zo = 177.6Ω
L = 642.9 pH/mm
C = 0.0465 pF/mm
R = 34.46 mΩ/mm
Delay = 530.4 ps

I get:

Zo = 117.6Ω (considerably off)
L = 642.8 pH/mm (only 0.1 ph/mm off)
C = 0.0465 pF/mm (same)
R = 9.072 mΩ/mm (considerably off) 
Delay = 530.3 ps (only 0.1 ps off)

Since some numbers, L, C, and Delay are equivalent or off by just a fraction, but Zo and R are considerably off, I'm a bit perplexed.

Oli Glaser gave a fantastic answer to a question regarding termination resistors: SDRAM Termination Resistors: Are They Needed?

I am trying to replicate his wCalc and SPICE simulation calculations for learning purposes.

I've got about everything figured out except how exactly he came to his wCalc results.

Here is a screenshot at my failed attempt of coming to the same result as Oli did using wCalc.

Oli gets:

Zo = 177.6Ω
L = 642.9 pH/mm
C = 0.0465 pF/mm
R = 34.46 mΩ/mm
Delay = 530.4 ps

I get:

Zo = 117.6Ω (considerably off)
L = 642.8 pH/mm (only 0.1 ph/mm off)
C = 0.0465 pF/mm (same)
R = 9.072 mΩ/mm (considerably off) 
Delay = 530.3 ps (only 0.1 ps off)

Since some numbers, L, C, and Delay are equivalent or off by just a fraction, but Zo and R are considerably off, I'm a bit perplexed.

Oli Glaser gave a fantastic answer to a question regarding termination resistors: SDRAM Termination Resistors: Are They Needed?

I am trying to replicate his wCalc and SPICE simulation calculations for learning purposes.

I've got about everything figured out except how exactly he came to his wCalc results.

Here is a screenshot at my failed attempt of coming to the same result as Oli did using wCalc.

Oli gets:

Zo = 177.6Ω
L = 642.9 pH/mm
C = 0.0465 pF/mm
R = 34.46 mΩ/mm
Delay = 530.4 ps

I get:

Zo = 117.6Ω (considerably off)
L = 642.8 pH/mm (only 0.1 ph/mm off)
C = 0.0465 pF/mm (same)
R = 9.072 mΩ/mm (considerably off) 
Delay = 530.3 ps (only 0.1 ps off)

Since some numbers, L, C, and Delay are equivalent or off by just a fraction, but Zo and R are considerably off, I'm a bit perplexed.