The following is a summary from Claude.ai about the debugging and problem I am facing, it was over a couple of days and working sessions, so I used the AI to summarize the data from me, which was unstructured bullet points and hard to follow. I have reviewed it for accuracy though.
HFSS 3D Layout: Encrypted 3D Component Bounding Box Intersection Hard Fail — Samtec GPPC
Software Version: Ansys HFSS 2025 R2
Design Type: HFSS 3D Layout
Issue Summary
I am getting a hard mesh fail when using an encrypted Samtec GPPC end-launch coax connector 3D component placed in HFSS 3D Layout. The simulation fails with:
- "Intersection(s) were found with the bounding box of hidden parts in component U1"
- "Model has geometry intersections"
Specific mesh error examples from the Mesh Feedback dialog:
Fill(Layer:L2_gnd, Net:<No-Net>) intersects with U1:Sheets:HFSSDesign1_1:Material4:WP_1Fill(Layer:L3_sig, Net:<No-Net>) intersects with U1:Sheets:HFSSDesign1_1:Material4:WP_2- (Same error repeating across multiple layers — L4_gnd, L5_sig, etc.)
The intersections are occurring at the front face of the 3D component, where the wave port (WP) sheets inside the encrypted component meet the PCB stackup layers.
Design Setup
- 16 layer PCB stackup
- Samtec GPPC end-launch coax connectors placed at the board edge
- 3D Placement is enabled on the component
- HFSS Mesh is checked and greyed out (forced on by the encrypted component — cannot be changed)
- The connectors are used as coaxial wave ports launching into the board
What Has Been Tried
Padstack with antipads on all layers — correctly voids copper and dielectric on every layer under the connector footprint. Verified working (no stray copper visible). Error persists.
Void polygons on individual copper fill layers — explicitly voided fills around the connector area. Error persists.
Cutting back the board edge — trimmed PCB geometry away from the connector interface face. Error persists.
Expanding the airbox — large padding added, airbox is not the issue. Error persists.
Mesh Fusion [Beta] enabled at the component level (via HFSS Mesh Settings on the component instance) — Mesh Fusion envelope visible in layout. Error persists.
Auto-resolve domain intersections — greyed out and unavailable even with Mesh Fusion enabled. Believed to be blocked because the component is encrypted.
"Enable Design-level intersection checks" in Design Settings → HFSS Meshing Method — was already unchecked. Toggling it makes no difference.
Moved entire design well inside a large airbox — confirmed not an airbox boundary issue. Error persists.
Best Guess at Root Cause
The WP (wave port) sheet objects inside the encrypted Samtec component extend to the front face of the component body — the interface plane where the connector meets the PCB. PCB copper fills on all layers extend to the same plane, causing HFSS to flag intersections between the WP sheets and the fill geometry.
Since the component is encrypted:
- Internal geometry cannot be edited
- HFSS Mesh setting is forced on and greyed out
- Auto-resolve domain intersections remains greyed out regardless of Mesh Fusion state
Question
Is there any way to resolve or suppress this intersection error for an encrypted vendor 3D component in HFSS 3D Layout? Specifically:
- Is there a way to enable Auto-resolve domain intersections for encrypted components?
- Is there a tolerance or override setting that would allow the simulation to proceed?
- Has anyone successfully simulated the Samtec GPPC (or similar encrypted end-launch coax component) in HFSS 3D Layout and found a working placement workflow?
Note: Samtec SI team has been contacted and is pending response. Looking for any community workarounds in the meantime.
