Also I'd personally not use curved wriggles. HF signals travel in a straight direction. With curves they start diffracting and start bouncing cross each other and might start to radiate or echo back.
mmmmm.... *stress*! anyone else feel the curves are "Bad"?
No. You've followed a bunch of very good advice about length matching, impedance etc. It looks like you've generally kept the pairs parallel through the curves, which is great.
If you have an easy option in your software to switch from 45 degree corners to smooth curves, I would do it - if there's not, don't worry.
If tight for space you can use 90% corners with a chamfered outer edge. I suppose the chamfer acts like a mirror.
The chamfer is there for impedance reasons, it's not a mirror, and note that a curve is preferred. You also run the risk of manufacturing problems by doing the chamfer - you're already at the minimum trace width, right?
As you've previously said, the old layout was further away from best practices, and *it worked*.
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On Fri, Aug 11, 2017 at 2:56 AM, Andrew Bolin fivepointpalmexplodingheart@gmail.com wrote:
Also I'd personally not use curved wriggles. HF signals travel in a straight direction. With curves they start diffracting and start bouncing cross each other and might start to radiate or echo back.
mmmmm.... *stress*! anyone else feel the curves are "Bad"?
No. You've followed a bunch of very good advice about length matching, impedance etc. It looks like you've generally kept the pairs parallel through the curves, which is great.
If you have an easy option in your software to switch from 45 degree corners to smooth curves, I would do it - if there's not, don't worry.
i did those by hand using the "accordian" feature
If tight for space you can use 90% corners with a chamfered outer edge. I suppose the chamfer acts like a mirror.
The chamfer is there for impedance reasons, it's not a mirror, and note that a curve is preferred. You also run the risk of manufacturing problems by doing the chamfer - you're already at the minimum trace width, right?
yehyeh
As you've previously said, the old layout was further away from best practices, and *it worked*.
but it was done by someone else and it didn't use curves.
l
arm-netbook@lists.phcomp.co.uk
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Andrew Bolin -
Luke Kenneth Casson Leighton