PCB Materials and Processing Considerations for Filter Design

Most RF wireless systems use many filters for multiple stages within a system. Good filter design can sometimes be very challenging due to several specifications and many tradeoffs which are typically encountered with filter design. Over time as electromagnetic modeling has improved, filter designs can be well defined in the design stage prior to any circuit fabrication. However there are several exceptions which can cause a fabricated filter to behave differently than its’ modeled results. This webinar will give details of some of these exceptions and how to account for these design variables.

The first portion of the webinar will discuss multiple material properties which should be considered in the modeling and simulation stages of filter design. Following, there will be several issues addressed which relate to PCB fabrication and can influence filter performance. Lastly, a simple yet effective concept will be discussed which allows very significant reduction of spurious harmonics for microstrip RF filters. Included in discussions will be some modeled results of different filters and a comparison with their measured results.

Agenda:

Material properties
Design Dk
Anisotropy
CTE and TCDk
PCB fabrication influences
Copper plating thickness variation
Final plated finish impact on loss and phase response
Soldermask
Composite materials used to suppress spurious harmonics
 

Presenter Bio:

John Coonrod is the Technical Marketing Manager for Rogers Corporation, Advanced Connectivity Solutions Division. John has 30 years of experience in the Printed Circuit Board industry. About half of this time was spent in the Flexible Printed Circuit Board industry regarding circuit design, applications, processing and materials engineering. The past fifteen years have been spent supporting High Frequency Circuit materials involving circuit fabrication, providing application support and conducting electrical characterization studies. John is the Chair for the IPC D24C High Frequency Test Methods Task Group and holds a Bachelor of Science, Electrical Engineering degree from Arizona State University.