ENGINEERING ANSWER
A 50-ohm trace width depends on dielectric height, design Dk, conductor thickness, solder mask and neighboring copper. There is no single RO4350B width that is correct for every stackup.
What to decide before release
Use the width solver for a first estimate, then send the complete cross-section to the fabricator. Agree whether the stated impedance tolerance applies to a coupon, the routed line or a measured fixture. Keep the reference plane continuous beneath the route.
Checks to put in your design brief
- Choose the actual core height
- Include finished copper in final verification
- Reserve room for the verified width
Important distinction
Our quick solver uses a zero-thickness, uncovered microstrip model. It is a starting point, not a fabrication release.
Sources & basis
Material facts follow the cited source. Design checks are preliminary guidance, not supplier process instructions.