RAYPCB · ENGINEERING GUIDE
Pyralux AP9111R: Power Trace Drop and Terminal Design
Pyralux AP9111R is a double-sided adhesiveless AP construction with RA copper. The controlled manufacturer PDF identifies 35 µm foil over a 25 µm dielectric. A current web table displays an inconsistent copper conversion for this family, so the PDF and the supplier's release document should govern the dimensional callout. This page concentrates on conductor drop and termination design.
Trace the complete power loop
Record the source, load and return route, including connector contacts and local neck-downs. The widest area of copper does not define the resistance of a path containing a narrow terminal. If the return shares a different layer or connector pin arrangement, model it separately. Keep permissible drop and allowable temperature rise as different requirements.
Construction and decision boundaries
| Review item | What this page establishes | What remains project-specific |
|---|---|---|
| Source conflict | Web copper unit conversion differs from PDF | Use controlled supplier release. |
| Electrical task | Route and return voltage drop | No thermal rating inferred. |
| Termination | Local support and conductor neck | Review force and resistance together. |
Work from final copper
The calculator takes finished width and thickness. For an assumed 100 mm conductor, 1 mm width and 35 µm copper, resistance is about 0.0491 Ω at the entered resistivity of 0.0172 Ω·mm²/m. At 1 A, that gives about 0.0491 V drop and 0.0491 W heating. The model does not determine the resulting temperature or a safe continuous current.
| Review item | What to establish |
|---|---|
| Source | Controlled foil gauge, not a conflicting web conversion |
| Power loop | Both paths and contact boundaries |
| Termination | Support and copper-width transition |
| Limit | Resistance is not a temperature-rise model |
Treat the terminal as a mechanical feature
A soldered lead, connector or fastener can load a thin flex section. Show the reinforcement and the transition into the free span. Review copper-width changes and contact geometry where strain or heat concentrates. An electrically adequate trace can still fail if the assembly transfers repeated bending into an unsupported joint.
Compare thickness with a stated objective
AP9131R changes the dielectric section, AP8515R changes the conductor class, and AP9222R introduces heavier copper. Reducing voltage drop with wider routing may be preferable to thickening every conductor, but the layout and packaging must permit it. Compare those alternatives using the same path, current and final geometry basis.
Plan electrical verification
Choose measurement points that separate the copper path from contact resistance when necessary. Record the measurement temperature and current method. An end-to-end continuity test alone may not resolve a small but consequential resistance change. If resistance is an acceptance characteristic, specify the method and limit with the drawing rather than relying on a material table.
Copper trace resistance and voltage drop
Copper trace resistance and voltage drop
Use the current inputs and keep the assumptions
Start with the example only to inspect the units and the calculation boundary. Replace every assumption with a value tied to your own document or measurement. An empty numeric field is not zero. The review-reference field is a local label; avoid entering customer names, confidential part numbers or other private information into a public worksheet.
After calculating, read the notes alongside the numerical result. Changing any input invalidates the displayed result and disables its download until you calculate again. For a comparison, keep the units, geometry, material condition and measurement boundary consistent. A long decimal result does not imply equally precise input data. The downloadable record stays on your device and can be attached manually to an inquiry. It is not automatically transferred into the Contact form.
If an input is unknown, identify the person or document needed to resolve it. Do not fill a gap with a favorable generic value simply to obtain a result. You can request a material or fabrication review without using the tool. The arithmetic illustrates a relationship; it does not accept a construction, certify a material, establish current pricing or replace a supplier process specification.
| Input | What to establish before using it |
|---|---|
| Review reference | Nonconfidential revision label. |
| Trace length · mm | Uniform straight conductor equivalent. |
| Finished trace width · mm | Minimum finished width for this scenario. |
| Finished copper thickness · µm | Measured or specified finished copper. |
| Current · A | DC current; no ampacity or temperature-rise approval. |
| Copper resistivity · Ω·mm²/m | Assumed value at a declared temperature; adjust from verified data. |
Optional cost comparison from your own allowances
Use a quotation or a clearly labeled internal assumption for each input. Keep the quantity, construction and inspection scope the same when comparing alternatives. This uncalibrated planning model adds entered values; it contains no current market rates and does not issue a RAYPCB quotation. You can contact the team without completing it.
Optional project allowance comparison
Ask for a route-focused proposal
Provide the net path, minimum widths, connector details, current profile and installed shape. State which losses or dimensions are fixed and which can change. Request the exact offered construction and source revision so that a web-table transcription cannot silently become a procurement requirement.
Test the complete power loop and isolate the loss source
| Review point | Input to record | Decision or verification |
|---|---|---|
| Copper segment | Use finished copper and the minimum trace width for each route segment. | Add segment losses instead of using the widest visible copper area. |
| Contact boundary | Provide access points on each side of the connector where practicable. | Compare conductor-only voltage drop with the end-to-end drop to identify contact contribution. |
| Duty | Specify continuous, pulsed and startup current separately. | Evaluate heating under the actual duty and installed support condition. |
Use the review points above alongside the worked example on this page. Record the chosen inputs with the drawing revision and send unresolved items with the enquiry. A supplier response should identify the proposed construction and the evidence needed for release.
Standards, source context and limits
Use the edition, amendment and material-document revision named in the purchase agreement. A standards title, marketing label or supplier product family does not establish that a particular lot meets a requirement. Public summaries are useful for scope; the controlled specification and applicable test method govern acceptance.
The examples on this page are illustrative engineering scenarios. They are not RAYPCB production records or guaranteed material values. Source links identify the organizations responsible for the referenced information. Confirm applicability to the exact grade, construction and test condition before carrying a number into a drawing or qualification report. For a flex board, distinguish the design requirements in IPC-2223, finished-board qualification and performance in IPC-6013, and the material scopes of IPC-4202, IPC-4203 and IPC-4204. These cover different deliverables; naming them does not certify the material or factory. State the contracted revision and applicable material sheet. Source review date: 3 October 2026. Legacy designation, present availability and an approved replacement are separate questions.
For fabrication scope and the agreed construction requirements, see PCB manufacturing.
