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Resolve conflicting table presentations

The global manufacturer portfolio distinguishes R-5775(G) from N-glass variants. One regional web entry inspected during research used repeated product naming and questionable units or dielectric fields. Do not copy those cells into a drawing without checking the controlled manufacturer sheet.

Use the original product documentation, construction table and supplier confirmation to establish the relevant data. A website display discrepancy is a reason to retain a source note, not a reason to invent a corrected value from memory.

Construction decisions at a glance

Build a line model for the supplied construction

Record core thickness, pressed prepreg, glass style, resin content, copper profile and finished line geometry. These inputs determine whether a catalog material comparison is relevant to the actual route. An impedance target by itself does not identify the copper-loss assumption.

The R-5775(N) guide addresses the low-Dk-glass alternative. If the construction changes from G to N, review the geometry and timing model explicitly instead of assuming the same line width and all other parameters remain valid.

Channel loss budget at one frequency

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 吃瓜tv quotation. You can contact the team without completing it.

Allocate the complete channel

The tool subtracts an entered routing contribution and fixed losses from a channel budget with reserved margin. The sample gives 2 dB remaining from a 20 dB budget after 5 dB fixed, 3 dB margin and 10 dB routing. These are educational values, not measured MEGTRON 6G performance.

Enter a complete routing-loss rate at the declared frequency. Df alone is not that rate. Keep connectors, packages and transitions in the model, and use the same reference planes when comparing a simulation with measured evidence.

Treat chemistry changes as material changes

The R-5375 guide covers a halogen-free MEGTRON 6 route with its own E and N constructions. A chemical requirement may motivate considering it, but the change also needs thermal, dimensional and electrical review.

Request the exact declaration required by the customer and retain the proposed replacement identity. A commercial statement that two products are similar should not replace the controlled material callout or the engineering approval of a new construction.

Keep special copper outside the ordinary assumption

The R-5775(S) buried-resistor page is relevant only when resistive foil is part of the circuit. Its sheet resistance, geometry and test requirements are additional construction details, not properties of an ordinary G-grade stackup.

Similarly, a low-profile foil description should identify the exact supplier data used in the loss model. Treat a proposed change in roughness or treatment as a potential electrical change, even if the nominal copper weight is unchanged.

Prepare an inquiry with a traceable baseline

Send the full material name, source revision, layer map, copper, dielectric dimensions, route lengths, frequency and loss allocation. Include the board size, quantity and required coupon or inspection scope. Flag any unresolved source-table discrepancy.

Compare prices only after the proposals describe the same deliverable. The optional allowance worksheet can retain user-entered costs and qualifications; it does not certify material authenticity, establish stock or replace a project-specific quotation.

Tie the exact grade to an electrical construction

State the channel reference planes, frequency range, routing length, copper construction, transitions and interface assumptions together. A laminate loss-tangent value is one input to that system. It is not a complete insertion-loss measurement or a guarantee that a data rate will work.

Use comparable measurement or modeling conditions when screening alternatives. Material changes can require geometry changes to preserve impedance, and copper roughness can alter the result independently of the resin system. Keep the proposed stackup and the channel analysis synchronized through fabrication review.

For procurement, identify the properties that are fixed and the alternatives that can be evaluated. Request evidence at the relevant construction and frequency rather than a broad low-loss label. Compare total delivered scope and validation effort alongside material price. A shorter or better-routed channel may change the tradeoff more than replacing a material name alone.

A useful design-data record retains both the material value and the reason it was selected. State whether the value is supplier characterization, a construction-specific design input, a measured coupon extraction or an early assumption. These sources are not interchangeable. Keep frequency, method and specimen information visible when a comparison uses more than one document.

The tool on this page starts empty because a plausible default can otherwise be mistaken for a verified grade profile. Use the example to understand the units, then replace it with project inputs. A result with many decimal places does not imply that the material or routing-loss input is known to that precision.

For a high-speed design, plan how the model will be checked. Reference planes, coupon geometry, fixtures and the acceptance boundary determine what a measurement means. A coupon that characterizes one line construction does not automatically qualify every route or transition on the board.

Keep the commercial comparison aligned with the engineering one. Quantity, copper, layer structure, test deliverables and qualification effort should be comparable. A lower material allowance can be irrelevant if the proposed construction cannot meet the channel requirement, while a premium grade may be unnecessary if the actual route already has sufficient validated margin.