High Frequency PCB Specifications
High frequency PCB boards are highly needed in satellite communications such as satellite framework and cell phone getting base station. Key elements of high frequency PCBs are as following:
a.Dielectric constant should be small and stable enough, ordinarily the littler the best, high dielectric constant may prompt sign transmission delay.
b.Dissipation factor should be small, which for the most part influences nature of flag transmission, the littler dissipation factor could make littler flag wastage as needs be.
c.The warm expansion rate should be the same as the copper thwart, but it is reasonable to expect that this distinction will prompt copper to be isolated in cold and warm processes.
d.Low water absorption; high water absorption will affect dielectric constant and factor in the wet condition.
In general, high frequency can be characterized as recurrences above 1 GHz. Currently, polytetrafluoroethylene (PTFE) materials are commonly used as part of high-frequency PCB production, it's likewise called Teflon, whose recurrence is ordinarily over 5GHz.. Similarly, FR4 or PPO substrates can be used for project between 1GHz and 10GHz. The three high frequency substrates have the following comparisons:
As to cover cost among FR4, PPO and Teflon, FR4 is the cheapest, while Teflon is the most expensive. Teflon is at its best in terms of dielectric constant and factor, water retention and recurrent. When product applications require repetitive frequencies more than 10 GHz, Teflon PCB substrates is a good choice for production.
Obviously, Teflon is much better than other ones since the Teflon substrate has the solidness and warmth opposing property work, countless or fiber glass as the filling material.