[Well replying from my phone did not work out at all. :-(]
Are you running multiple channels?
When you do your analysis, be careful to look at the effects of
crosstalk on adjacent lines. The cross hatching will distort the return
currents, pushing them closer together.
If you're running high enough data rates to be concerned about surface
roughness or fiber weave, you won't be happy with the cross hatch.
BTW, I'm no thermal expert, but how does the cross hatch improve thermal
issues? The hatch has less copper with a smaller, more restrictive
profile, so it should act as a thermal resistor. Any thermal problem
I've come across needed more copper, not less, but I suppose there could
be instances where you'd want to restrict heat transfer.
Alan Hilton-Nickel
On 4/7/2017 6:43 PM, Bert Simonovich (Redacted sender bertsimonovich for
DMARC) wrote:
I agree with Ryan and Al on using a good field solver for accurate impedance
and loss modeling over frequency. I recently benchmarked both Polar Si9000
Transmission Line Field Solver and Simbeor by applying my Cannonball
modeling technique to the Huray roughness model and compared results against
de-embedded measured data from Al's CMP28 Wildriver modeling platform. Both
tools gave excellent correlation to ~50GHz.
Bert Simonovich
Signal/Power Integrity Practitioner | Backplane Specialist | Founder
LAMSIM Enterprises Inc.
Web Site: http://lamsimenterprises.com
Blog: http://blog.lamsimenterprises.com/
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On
Behalf Of Alfred P. Neves
Sent: 7-Apr-17 8:09 PM
To: rdawson16@xxxxxxxxxxx
Cc: si-list
Subject: [SI-LIST] Re: flex crosshatch reference plane and LVDS differental
pairs
Actually, the new Polar tools are pretty good at estimating impedance over
frequency, some of the most popular EDA tools that you may have been using
are horrid, however. The data was taken using our Channel Modeling
platforms and speaks to the necessity of careful benchmarking even an EDA
package that costs upwards of $100K.
As Ryan stated, we are also using Simbeor due its cost/performance and
accurate loss modeling.
- Al
Products for the Signal Integrity Practitioner
Alfred P. Neves
Chief Technologist
Office: 503-679-2429
www.wildrivertech.com <http://www.wildrivertech.com/>
2015 Best In Design&Test Finalist
On Apr 7, 2017, at 4:26 PM, Randy Dawson <rdawson16@xxxxxxxxxxx> wrote:from a few engineers that impedance calculators (Polar) are not so accurate.
I am looking for SI articles on this and not finding much. I have heard
I am also reading that I should expect some attenuation GHz frequencies. I
am forced into crosshatch vs solid due to thermal issues.
I do have the Sigrity field solver and will experiment and let you knowwhat I find.
What are you're experiences with this?
Randy
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List forum is accessible at:
http://tech.groups.yahoo.com/group/si-list
List archives are viewable at:
//www.freelists.org/archives/si-list
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List forum is accessible at:
http://tech.groups.yahoo.com/group/si-list
List archives are viewable at:
//www.freelists.org/archives/si-list
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
---
This email has been checked for viruses by AVG.
http://www.avg.com
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List forum is accessible at:
http://tech.groups.yahoo.com/group/si-list
List archives are viewable at:
//www.freelists.org/archives/si-list
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
