// PCBSync Engineering Tools
Everything an RF engineer needs to design with RT/duroid 5880 — the low-Dk, ultra-low-loss PTFE laminate behind radar, antenna and mmWave boards. Live impedance & trace-width calculators, full material data (Dk 2.20), design tips, manufacturing notes and cost guidance, in one place.
Ready for fabrication? Order your Rogers 5880 PCB from PCBSync.
// 01 — Engineering Tools
Closed-form RF tools tuned to RT/duroid 5880 (εr 2.20). Synthesize trace widths, check impedance, and size wavelengths for stubs and antennas. Results update instantly as you type.
Closed-form Wheeler/IPC-2141 (microstrip) and Cohn/IPC (stripline) approximations, εr = 2.20. For controlled-impedance builds, confirm against your fabricator's stackup & a 2D field solver — etch shape, copper roughness and solder mask shift real values.
λ₀ = c/f, λg = λ₀/√ε. Use ε = 2.20 for embedded (stripline) lines on 5880, or the effective εeff from the impedance tool for microstrip. Quarter-wave (λg/4) sizes open/short stubs, matching transformers and patch dimensions.
// 02 — Material
Rogers RT/duroid 5880 is a PTFE composite reinforced with randomly-oriented glass microfibers. Its very low, stable dielectric constant and exceptionally low loss make it a benchmark for high-frequency and high-reliability RF designs.
| Dielectric constant, Dk (εr) @ 10 GHz | 2.20 ± 0.02 |
|---|---|
| Dissipation factor, Df (tan δ) @ 10 GHz | 0.0009 |
| Thermal coefficient of εr | −125 ppm/°C |
| Volume resistivity | 2 × 10⁷ MΩ·cm |
| Surface resistivity | 3 × 10⁷ MΩ |
| Thermal conductivity | 0.20 W/m·K |
| CTE (x / y / z) | 31 / 48 / 237 ppm/°C |
| Moisture absorption | 0.02 % |
| Density | ≈ 2.2 g/cm³ (lowest of Rogers laminates) |
| Flammability | UL 94 V-0 |
| Copper cladding | ½, 1, 2 oz (ED & rolled) |
RT/duroid 5880LZ is a lighter-weight variant with an even lower Dk of 1.96 and reduced density — favored for weight-critical airborne and space arrays. Standard 5880 remains the go-to general-purpose low-Dk laminate.
// 03 — Design Tips
Practical guidance for getting predictable, low-loss RF performance from RT/duroid 5880 — from trace geometry to thermal and copper choices.
Low Dk (2.20) means 50 Ω lines run wide — roughly 3× the substrate height. Budget board area early and watch coupling between adjacent RF lines and bends.
Trapezoidal etch profiles and ±tolerance shift impedance. Design from your fab's actual etch factor and use an impedance-controlled stackup with TDR coupons for tight targets.
At mmWave, conductor loss from copper roughness dominates. 5880 is offered with rolled / low-profile copper — call it out in your loss budget for radar and antenna feeds.
Use proper plated through-holes and, above ~20 GHz, back-drill to remove via stubs. Model launch transitions; they often limit real-world insertion loss.
The −125 ppm/°C Dk coefficient gives excellent phase stability over temperature, but thermal conductivity is low (0.20 W/m·K). Use copper pours, thermal vias or coins to move heat.
Solder mask adds loss and detunes RF lines — many 5880 boards run bare or selectively masked. For digital+RF, bond 5880 to FR-4 with a proper bond-ply and account for CTE mismatch.
// 04 — Manufacturing
PTFE laminates demand process expertise. Knowing what the fab needs up front keeps yields high and avoids surprises on RF-critical boards.
PTFE is naturally non-stick, so plated holes need plasma or sodium-etch activation for reliable copper adhesion. Skipping this risks barrel separation in thermal cycling.
Sharp tooling and tuned feeds/speeds prevent smear and burring in the soft composite. Smear removal and debris control protect impedance and reliability.
Multilayer PTFE builds use high-temperature fusion bonding or thermoset bond-plies. Specify a fabricator experienced in Rogers laminates and mixed-dielectric stackups.
±10% is routine; ±5% is achievable with coupon TDR testing. Provide a target impedance and reference stackup so the fab can adjust line widths to hit it.
ENIG and immersion silver are common for RF. Plated edges and castellations are available for connector launches, shielding and module mounting.
5880 is dimensionally stable with very low moisture uptake, but mechanically soft — careful handling and panel utilization matter, since material is the dominant cost.
// 05 — Cost
As a premium PTFE laminate, material is the biggest cost lever — but build complexity matters too. Use this indicator to see how choices push relative cost, then get an exact quote.
This is a relative indicator of how your selections trade off — not a price. PTFE material, low volumes and bonded multilayers raise cost most. For an exact, manufacturable quote on your Rogers 5880 PCB stackup:
Get an exact quote from PCBSync// 06 — Applications
Low loss, stable Dk and low moisture uptake make RT/duroid 5880 a default choice wherever signal integrity at high frequency is mission-critical.
Automotive 24/77/79 GHz & defense radar front-ends and arrays.
Patch, phased-array & feed networks needing tight, repeatable impedance.
Low outgassing & moisture, stable Dk for SATCOM and spaceborne payloads.
Filters, couplers, power dividers & amplifier boards into the mmWave bands.
mmWave small cells, base-station front-ends & high-throughput links.
EW, secure comms & sensor electronics demanding high reliability.
Calibration standards & instrumentation needing low, predictable loss.
Microwave imaging & ablation systems requiring stable RF behavior.
// 07 — FAQ
// PCBSync
From radar arrays to mmWave front-ends, PCBSync builds RT/duroid 5880 boards to spec — impedance-controlled, RF-finished and tested. Bring your stackup; we'll handle the PTFE.
