Intel 820E Manual De Usuario

Design Guide 

 

179 

Though numerous stack-up variations are possible, the following starting point is recommended: 

W = 18 mils, H = 4.5 mils, T = 2.0, 1-ply 2116 prepreg 

For other possibilities see the following table and the following figures: 

Ω

Ω

Ω

Ω

1  27.1 4.3 18.0 2.1  0.6 53.0 

2  28.1 3.8 18.5 1.6  1.2 72.0 

3  28.6 4.8 19.0 2.5  0.7 61.0 

Inner-layer routing also has many possible stack-ups. For inner-layer routing, it is advisable to use the 
following starting point: 

W = 13.5 mils, H1 = 7 mils, H2 = 5, T = 1.2 

If these parameters are used, the initial TDR should fall within the acceptable limit, 28 

Ω

 ± 10%. 

Figure 98 shows examples of both stripline and microstrip cross sections.