差分计算器

suicide915

请问16.3中的差分计算器有什么作用

怎样使用呢
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kangpeng

参考第19页。希望有用。

kangpeng

Using the Differential Calculator
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Use the Differential Calculator to perform what-if scenarios to determine what combinations of line width and primary gap values can help you obtain a particular differential impedance. The calculator is available from the Electrical CSet- and Net worksheets.
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' l/ i  a) d8 u! ]: @You can perform calculations only for edge-coupled differential pairs on a selected ETCH/CONDUCTOR layer and account for material, thickness, electrical conductivity, dielectric constant, loss tangent, and shield.



3 _7 `) k( T" ^7 CLayer name
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& c" T& a. W5 M1 _! ^' h/ w, yIndicates the ETCH/CONDUCTOR layer for which you are running the calculation. By default, the TOP/SURFACE layer appears.

4 U7 u, C9 T& \7 u$ I( \8 l6 F6 sDifferential impedance
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" P% k6 s5 J+ l( m) l' jSpecifies the impedance of the differential pair. Calculated for a pair of lines having the specified Line width and Primary gap on the layer.
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( t% @* x7 g* @5 I! {) DSingle-line impedance
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Indicates the impedance of one line of etch on the selected layer.
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Changing this value automatically recalculates the Line width field. Each time the Line width field in this calculator changes--either when you directly modify it or when you select it to be recalculated--this value is recalculated, too.

Line width

/ H( c. \# u) v3 ?Specifies the minimum width of each line of the differential pair. Changing this value automatically recalculates the Single-line impedance field. And changing the Single-line impedance field automatically recalculates this value.
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Primary gap
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9 T6 t) E( }. `# x! jIndicates the ideal edge-to-edge spacing between the pair that should be maintained for the entire length of the pair.
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kangpeng

你在allegro constraint manager界面。按F1按钮，然后 在右上角搜索differential calculator,查看官网的帮助说明

ggbingjie

在哪个菜单下啊？

kangpeng

打开约束管理器

kangpeng

how to open differential calculator

suicide915

谢谢kangpeng
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9 F( `# F6 n& u' ?  b+ _9 H: X这个工具是否就是帮助计算合适的线宽线距以实现想要的差分阻抗？
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布板时大家有用到这个工具么？

另资料中提到的“仅能完成边对边耦合的差分对计算”是什么意思
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6 T( @0 l7 e: ^* T除了边对边耦合，还有哪些耦合
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