RO4830 is a spread-glass thermoset laminate documented in the selector for millimeter-wave work. Its 77 GHz Design Dk is distinct from its 10 GHz process Dk. This page keeps the original grade separate from RO4830 Plus, because the Plus material uses a different reinforcement approach and different electrical values.
Material system
Ceramic-filled hydrocarbon thermoset with spread woven glass
Technical properties
| Property | Reported value | Conditions / source |
|---|---|---|
| Process dielectric constant | 3.25 ± 0.05 | Typical, 10 GHz, 23°C; IPC-TM-650 2.5.5.5 clamped stripline; direction is not separately recorded here. Source |
| Design dielectric constant | 3.24 | Typical; 77 GHz, microstrip differential phase length method. Do not relabel this observation as a 10 GHz measurement. Source |
| Dissipation factor | 0.0033 | Typical, 10 GHz, 23°C; IPC-TM-650 2.5.5.5; direction is not separately recorded here. Source |
| Thermal conductivity | 0.45 W/(m·K) | Typical; selector guide laminate table, ASTM D5470 at 50°C. Table does not identify axis. Source |
Typical reported values are not a purchase specification. Process Dk, design Dk and values measured at different frequencies are not interchangeable.
Selection and design notes
- For an existing RO4830 radar board, begin with the original stackup and foil specification before considering a material refresh. Preserve antenna and launch measurements so that a substitute can be assessed against actual performance.
- A move to RO4830 Plus is a redesign decision. Recalculate the RF layer, review the reinforcement change and reproduce the antenna environment rather than replacing the name in the bill of materials.
Thickness and copper options
The selector is a reference only; confirm the original RO4830 core thickness and tolerance for an offered batch.
Do not reuse RO4830 Plus copper details for original RO4830. Obtain the exact original-grade foil designation.
Fabrication considerations
- Confirm that the fabricator can identify the supplied RO4830 construction and its applicable processing instructions. Thin RF cap layers require control of dielectric thickness, etch geometry and transitions into lower-frequency layers.
Application fit
- Existing millimeter-wave boards
- Radar material comparisons
- RF cap-layer references
Limits and substitution checks
- The current family page emphasizes RO4830 Plus, while the original RO4830 remains in the selector. This is not enough to declare the original discontinued or currently available. The entry uses selector-backed data and withholds automatic calculation presets pending a current grade-specific datasheet and supply confirmation.