Things to be considered when designing via for high speed signals

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hioyo

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Dear Team,

This is a general question.
May I know what are the things to be considered when designing VIAs for high speed design

Regards
HAu
 

Solution
Via impedance is typically specified for single ended wires, a single via embedded by plane copper. If you use two of this vias for your differential pair, they should have 50 ohm impedance each. But more likely the vias of a differential pair are closer together and not completely embedded by copper. Respectively the impedance is different.
Height. Width. Hole diameter. Plating thickness. Inductance. Capacitance. Impedance.
Thank you..
If I am designing the via for a 100ohm differential trace then the Via impedance must be 100ohm.Please correct
me if I am wrong
 

There's no thing like a "100 ohm via". Transmission lines have differential and common mode impedance. You are designing a differential transmission line.
 
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    hioyo

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There's no thing like a "100 ohm via". Transmission lines have differential and common mode impedance. You are designing a differential transmission line.
Okay you mean entire transmission line inculding via should have an impedance of 100ohm.I am I correct
 

Via impedance is typically specified for single ended wires, a single via embedded by plane copper. If you use two of this vias for your differential pair, they should have 50 ohm impedance each. But more likely the vias of a differential pair are closer together and not completely embedded by copper. Respectively the impedance is different.
 
Reactions: hioyo

    hioyo

    Points: 2
    Helpful Answer Positive Rating
Solution
Dear Team,

This is a general question.
May I know what are the things to be considered when designing VIAs for high speed design

Regards
HAu
The following are the factors that must be considered. Plating thickness
Capacitance.
Hole diameter.
Inductance.
Impedance.
Width
Height.
 

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