RO4350B PCB Manufacturing & Stackup Design
Turn your RF design into a clear fabrication request: check trace geometry, define the construction and prepare a quote brief.
Design & Specify Your RO4350B PCB
Check a design decision. Record assumptions. Prepare a useful fabrication enquiry.
Start with a supplier thickness
Choose a catalogue core or keep a custom design dimension. Applying a thickness changes the local microstrip height, not the finished board thickness.
No catalogue construction applied yet.
Compare two thickness choices at the same impedance
This Line design tab uses a preliminary zero-thickness, quasi-static model. For finite copper or GCPW, use the separate advanced calculation below. This reference model excludes solder mask, finite copper, roughness, vias and connectors. Confirm the exact stackup with a field solver and fabricator. Frequency is not a material-dispersion model. Microstrip h / free-space wavelength must be 鈮� 0.05.
Width, dielectric height and model-Dk sensitivity
Reference ground below 鈥� schematic, not an approved stackup
Finite-copper microstrip and grounded CPW
A mask or cover changes the field distribution. This worksheet records it for solver review rather than applying an unsupported universal Dk adjustment.
Build a layer-by-layer discussion stackup
Select a copper-layer count, then name and dimension every core and bond layer. Blank thicknesses are unresolved; they are never silently treated as zero.
Loading an example replaces this worksheet. Copper defaults are illustrative. Bond product, cured thickness and internal support thickness must be supplied; no lamination approval is implied.
View the layer-sequence schematic
Transfer uses only a named material core between L1 RF and L2 ground. No averaged mixed-dielectric Dk is created.
Shares the inputs in Line design. Change the geometry there before calculating this task.
Download the brief and attach it with your design files. Contact opens the enquiry page; parameters and files are not automatically transferred. Email opens a draft for you to review.
No enquiry has been sent. Calculations remain in this browser.
RO4350B thickness and copper options
吃瓜tv can procure Rogers-offered materials and thicknesses. Select the exact construction for your request; available stock, copper combination, minimum purchase and delivery date are confirmed for the order.
| Nominal dielectric | Metric conversion | Supplier thickness tolerance | Construction note |
|---|---|---|---|
| 4 mil | 0.1016 mm | 卤 0.7 mil | 4 mil Process Dk is 3.33 +/- 0.05. Do not automatically substitute Process Dk for Design Dk; confirm a construction-specific design model. |
| 6.6 mil | 0.1676 mm | 卤 0.7 mil | |
| 10 mil | 0.2540 mm | 卤 1 mil | |
| 20 mil | 0.5080 mm | 卤 1.5 mil | |
| 30 mil | 0.7620 mm | 卤 2 mil | |
| 60 mil | 1.5240 mm | 卤 4 mil |
These are supplier catalogue dielectric dimensions, not finished PCB thickness or inventory. Metric values above are converted from the listed inch dimensions. A catalogue dielectric tolerance is not a guaranteed impedance tolerance.
Specify the cladding separately
- Electrodeposited copper, 0.5 oz (18 碌m nominal) 鈥� Base foil, not finished plated copper. Confirm the thickness/foil combination and roughness for the actual order.
- Electrodeposited copper, 1 oz (35 碌m nominal) 鈥� Base foil, not finished plated copper. Confirm the thickness/foil combination and roughness for the actual order.
Process Dk tolerance is a supplier-test specification, not an automatic Design Dk uncertainty band. Standard ED codes are HH/HH for 0.5 oz and H1/H1 for 1 oz. LoPro uses reverse-treated foil with a modified bonding resin, adding approximately 0.7 mil (18 碌m) per core. Confirm actual construction thickness and model Dk; do not treat it as the unchanged standard core. RO4350B LoPro has a different UL designation from standard RO4350B; confirm applicable qualification. Additional non-standard thicknesses 6.6鈥�60 mil are described in varying increments, without one common tolerance.
. Procurement availability confirmed by 吃瓜tv on 17 October 2026; this is not a stock or lead-time promise.
Choose the construction before locking the line width
A material name alone does not define an RF board. The distance from the signal to its reference plane controls the line model; the overall finished board thickness does not substitute for that distance. Decide which layers carry RF, where their continuous return planes sit, and which dielectric each field crosses before asking for an impedance value. Keep the RF geometry and the mechanical thickness requirements separate in the fabrication drawing.
Standard, 4 mil or LoPro?
The datasheet lists a separate 4 mil process Dk of 3.33 卤 0.05. LoPro constructions also require their own foil and dielectric definition. This workbench starts with the standard Design Dk, not a claim that one value covers every cladding and thickness.
Use a controlled drawing and material specification to identify the ordered construction. A product photograph cannot verify laminate grade, dielectric properties or inspection results.
Keep the material data and design model connected
| Reference quantity | Value | How to use it |
|---|---|---|
| Process Dk | 3.48 卤 0.05 | Supplier test reference; do not use its tolerance as a guaranteed Design-Dk tolerance. |
| Design Dk | 3.66 | Starting model value, subject to exact construction and appropriate frequency data. |
| Df at 10 GHz | 0.0037 | Dielectric reference only; not total circuit insertion loss. |
| TCDk | 50 ppm/掳C | Typical coefficient; not a life or system-qualification model. |
Process Dk / Df: 10 GHz, 23 掳C, IPC TM-650 2.5.5.5; Design Dk: 8鈥�40 GHz differential phase length; TCDk: 鈭�50 to 150 掳C. Typical source values, not finished-board acceptance limits. In this workbench, Dk and frequency are explicit inputs; no dispersion curve is inferred. Catalogue constructions must be checked for the actual order.
Data checked 17 October 2026 against the . Use the current supplier document when releasing a design.
Choose a layer structure for the RF task
Start with the signal and its reference plane, then add routing, power and mechanical requirements. The workbench records each conductor and dielectric separately. Example layer allocations are discussion starting points, not released manufacturing constructions.
| Architecture | Decision to resolve | Useful next step |
|---|---|---|
| Two copper layers | RF signal on one face, continuous ground on the other. The core is the local dielectric; finish, mask and launches remain separate inputs. | Use the line and thickness comparison tools above. |
| Four copper layers | Define the outer RF cores and central bonding construction; decide whether both faces carry RF. | Review four-layer PCB fabrication and four-layer stackup choices. |
| Six copper layers | Keep RF paths beside continuous grounds while allocating internal power and routing. Specify the FR-4 or RF support core and both bond layers. | Define a six-layer PCB build; use the six-layer stackup guide for layer allocation. |
| Eight or more layers | Resolve additional routing, via transitions, lamination sequence and mechanical balance before freezing dimensions. | Review eight-layer fabrication requirements or discuss a specific construction. |
| RF / FR-4 hybrid or metal-backed build | Specify every bond product, cured thickness, interface and thermal requirement. The online tool does not approve a press cycle or adhesive system. | Use the Rogers multilayer construction guide. |
For other layer counts, follow the multilayer PCB manufacturing route. Material-specific construction and RF acceptance remain part of the RO4350B enquiry.
Hybrid construction
A local RF layer can coexist with FR-4 support layers, but the bond layers, thermal behavior and fabrication sequence must be agreed. The construction worksheet adds explicit thicknesses; it never averages RF and FR-4 Dk into a fictional substrate.
A useful impedance request
Specify the signal layer, reference plane, finished trace width, local dielectric thickness, copper and mask. Agree the coupon geometry, test method and acceptance tolerance. A nominal 50 惟 calculation alone does not establish a testable purchase requirement.
A starting geometry you can reproduce
For a 50 惟 exposed microstrip using model Dk 3.66, local dielectric height 0.2540 mm and a 10 GHz calculation frequency, this model gives a starting width of 0.5567 mm and effective permittivity 2.8582. A uniform 50 mm path has an unwrapped phase of 1015.08掳. These are calculated examples, not measured board results.
Reproduce the values in Line design, then change one input. Before release, replace the example with the agreed construction, include finite copper and mask in an appropriate solver, and confirm how the finished board will be inspected.
Turn design choices into acceptance requirements
| Decision | Include in the RFQ | Resolve before release |
|---|---|---|
| RF layer pair | Layer names and an uninterrupted ground reference | Is the dielectric between these layers the specified construction? |
| Copper and finish | Base / finished copper, foil type, finish and mask openings | Which features require a finite-thickness or roughness model? |
| Mixed stack | RF cores, FR-4 cores and cured bond thicknesses | What needs lamination, registration or reliability review? |
| Acceptance | Impedance limits and coupon / measurement details | Do coupon and board represent the same geometry? |
Ask for confirmation against the released construction and files. The planning result is a discussion aid; the accepted drawing, quotation and inspection scope define the order.
Connect the drawing, the board and its test record
For your RO4350B build, identify the evidence needed before ordering. A useful review connects the same material designation and drawing revision across the stackup, physical inspection and electrical test. The catalogue photograph on this page gives construction context; it does not establish order-specific material identity or RF performance.
Illustrative evidence workflow, not a sample inspection report. Request applicable records and agree availability before purchase. RF measurement scope, calibration, fixture correction and environmental testing must be specified; they are not automatically included in a continuity test.
Start the enquiry at your current design stage
| Your stage | Useful starting information | Request |
|---|---|---|
| Selecting a material | Frequency band, mechanical envelope, environment and material candidates. Final artwork is not needed to describe the question. | Check material availability |
| Designing the PCB | Proposed layer sequence, RF reference planes, dielectric / copper dimensions and unresolved requirements. | Request a stackup review |
| Ready for fabrication | Released artwork and drill files, drawing revision, quantity, material specification and acceptance requirements. | Get a quote for this build |
Use the workbench to download a brief if it helps explain the project, or contact the team directly. These links open Contact; they do not upload files or automatically submit tool inputs. Ask the team to confirm the available review scope and quotation requirements.
RO4350B design & procurement questions
Should I enter 3.48 or 3.66?
Use a design value appropriate to your construction and model. The process value describes the supplier test method; it is not interchangeable with the published Design Dk. Keep the source and test conditions with the number.
Does hybrid construction always cost less?
No. Reducing premium laminate area may be offset by bonding, registration, additional process steps and verification. Compare itemized quotations for equivalent acceptance scope.
Can I approve the calculated width for production?
Treat it as a starting point. Confirm finished copper, mask, foil, etch compensation and the fabricator鈥檚 field-solver stackup before releasing artwork.
Continue with the decision you need to make
For a different material route, compare the Rogers material families. Use the relevant construction or acceptance guide when the requirement goes beyond this material-specific model.
Model references & limits
The reference line tool uses a zero-thickness approximation; the advanced tool separately identifies finite-copper and grounded-CPW models. Corner results are deterministic bounds from your entered scenarios; no statistical capability is inferred. Measurements and a construction-specific field solver remain the appropriate next steps for release.
- : material values and test conditions.
- : Hammerstad鈥揓ensen geometry formulation.
- : quasi-static mapping and limited finite-copper correction.
- : implementation convention cross-check; not a measured accuracy claim.