RO4000 LoPro identifies a smooth reverse-treated copper construction used with several RO4000 laminates, rather than one dielectric formulation with a universal Dk. Its engineering value is reduction of the conductor-profile contribution to transmission-line loss. The base core grade, added bonding resin, thickness and foil weight remain essential parts of its identity.
Material system
RO4000 core variants with modified resin interface and reverse-treated LoPro ED copper
Technical properties
| Property | Reported value | Conditions / source |
|---|---|---|
| No verified scalar property set is available here. Use the original product documentation and confirm the ordered construction. | ||
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
- Consider LoPro where long microwave traces or millimeter-wave circuits make copper roughness a significant fraction of the loss budget. Compare complete transmission lines with matched geometry and foil, not laminate Df in isolation.
- Choose the base material first. RO4003C LoPro and RO4350B LoPro have different starting dielectric systems and cannot share one anonymous material preset.
- Document the approved construction in the simulation library.
Thickness and copper options
Thickness is base-core and construction dependent. Consult the LoPro table rather than adding copper thickness to a standard-core dimension by assumption.
LoPro is reverse-treated ED copper with a resin interface. CU4000 LoPro is a companion foil product, not a synonym for every LoPro-clad core.
Fabrication considerations
- Tell the fabricator that the laminate uses LoPro and identify foil-side orientation. For foil-laminated multilayers, the CU4000/CU4000 LoPro document is a separate compatibility reference; it does not authorize replacing any inner-layer foil without checking the bonding system.
Application fit
- Low-loss transmission lines
- Microwave multilayers
- Millimeter-wave feed networks
Limits and substitution checks
- A nominal 0.7 mil core-thickness addition and thickness-sensitive effective Design Dk are noted in the RO4000 datasheet. No single numerical preset is supplied here because suppressing those construction differences would create false precision in impedance calculations.