Mixed Dielectric Approach Accelerates Digital Applications April 2001 Issue Published Date: April 01, 2001
Addressing the needs of today's electronic systems designers for increased signal speeds and densities, a mixed dielectric approach combines standard fiberglass reinforced materials for non-critical signal layers such as power and ground planes with a low dielectric constant, low loss prepreg, Speedboard C, for critical signal layers. In addition to its use in mixed dielectric constructions, Speedboard C prepreg is well-suited for use in high-speed digital applications. It is also said to be an optimum choice to replace thermoplastic fluoropolymer bondfilms and fusion bonding processes in PTFE microwave PWBs. Multiple plies of prepreg can be used to obtain a wide range of dielectric thickness for controlled impedance layers. In addition, Speedboard C prepreg is UL94-V0 certified and NASA approved for space applications. It also affords very fast laser drilling speeds when utilized as an outer layer dielectric for microstrip designs.
