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SYiwe's avatar
SYiwe
Icon for Occasional Contributor rankOccasional Contributor
6 years ago

How can I convert "ps" to "mil" in EMIF layout guidelines?

Some design guidelines in EMIF user guide use "ps" as unit, as you can see in the following screenshot. But in the pcb design, I must check the route lines by mils or millimeter, how can I convert "...
ak6dn's avatar
ak6dn
Icon for Regular Contributor rankRegular Contributor
6 years ago

Well, all the physical devices care about is ps of timing delay for aligning signal edges.

When it comes to converting ps of delay to mils of trace length, it depends entirely on your PCB implementation.

Whether you are using stripline, microstrip, or embedded microstrip, and the dielectric material of your PCB all determine the Tpd or ps/mil delay factor for your PCB.

Most PCB layout tools have calculators that allow you to enter the stackup configuration and Er (dielectric constant) of your PCB material so they can compute Tpd.

Some PCB layout packages allow you to enter net length parameters in terms of 'ps' instead of 'mil' (or 'mm') but again you must configure the detailed stackup.

So if none of this makes any sense to you I suggest you find an SI (Signal Integrity) guy in your organization to help you.

SYiwe's avatar
SYiwe
Icon for Occasional Contributor rankOccasional Contributor
6 years ago

Thanks.

Is Tpd the time delay which the signal propagate in 1 mil?

The unit of Tpd is ps/mil, is that correct?

Regards.