Hello All ,
Any update on the question raised ?
I'think you may layout your differential pairs by 5.5mil width and 7mil for clearance between the two traces.
The "2W" value is the clearance against all the others traces presents on your board.
So you have to ensure that any signal keep 14mil clearance from diffenrential traces.
Hello Vincent ,
Thanks for the useful information .
But here my concern is related to spacing between differential signals and not spacing of differential pair to other signal .
Should the clearance between differential signals ( + and - ) be 2W or greater than 2W or less than 2W and also why ?
Best Regards ,
The clearance within differentials pairs depend,as you know,on topology,materials,traces width,traces thickness,traces separation,distance to reference planes and so on.
In most cases, the values calculated ,based on trace width,are closed to 2W,but it is not a formal law (as I know) since there is a lot of possible combinations dependin on the stackup selected.
I'think that "2W" is an approach to find the ideals values.
Differencial pair routing has the purpose of increase the noise inmunity and reduce emitted electromagnetic radiation. Controlled impedance and length matching are critical, the 2W rule does not apply between diff pairs, the spacing is calculated acording to the stack up of the board.