Add impedance-controlled netclasses for 4-8L stackups #62
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
akhilles
force-pushed
the
add-netclasses
branch
3 times, most recently
from
449b683 to
101ee2e
Compare
(50Ω SE, 85Ω/90Ω/100Ω differential) covers USB 2.0/3.x, PCIe, Ethernet, HDMI, DisplayPort, LVDS, MIPI, plus all the 50Ω single-ended protocols (SD cards, SPI, RF, etc.). The trace widths and separations were calculated using the sierra circuits solver (https://impedance.app.protoexpress.com/) with 0.2mm coplanar gap and documented soldermask assumptions. The coplanar gap was set as the netclass clearance, but additional care might be necessary to ensure the ground pour meets this gap. Signed-off-by: akhilles <akhilvelagapudi@gmail.com>
Signed-off-by: akhilles <akhilvelagapudi@gmail.com>
Signed-off-by: akhilles <akhilvelagapudi@gmail.com>
Signed-off-by: akhilles <akhilvelagapudi@gmail.com>
Signed-off-by: akhilles <akhilvelagapudi@gmail.com>
akhilles
force-pushed
the
add-netclasses
branch
from
101ee2e to
1d37b81
Compare
hexdae
approved these changes
Oct 15, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
(50Ω SE, 85Ω/90Ω/100Ω differential) covers USB 2.0/3.x, PCIe, Ethernet, HDMI, DisplayPort, LVDS, MIPI, plus all the 50Ω single-ended protocols (SD cards, SPI, RF, etc.).
The trace widths and separations were calculated using the sierra circuits solver (https://impedance.app.protoexpress.com/) with 0.2mm coplanar gap and documented soldermask assumptions.
The coplanar gap was set as the netclass clearance, but additional care might be necessary to ensure the ground pour meets this gap.