In collaboration with Microwave Journal’s Technical Education Training Series, John Coonrod of Rogers Corp.’s Advanced Connectivity Solutions will present a one-hour webinar on “The Impact of Plated Through Hole Via’s on RF Performance,” on Thursday, April 6, starting at 8 AM PT/11 AM ET.

Overview of webinar: Plated through hole (PTH) via’s are commonly used for RF PCB applications. The use of PTH via’s for grounding or repetitive grounding is a typical application. However, when PTH via’s are used to transition a signal trace from one copper wire to another, the via property can have a significant impact on signal integrity.

This webinar will present an overview of several studies that evaluated the impact of PTH via’s on RF performance when transitioning the signal trace to different copper wires within a multilayer PCB. The test vehicle used is a multilayer circuit in a stripline configuration designed to demonstrate the impact of transitioning the signal trace from one copper later to another while maintaining the stripline structure.

These signal transitions are less problematic at lower frequencies (< 2 GHz); however, at higher frequencies such transitions can cause reflections, poor return loss, impedance ringing and degraded insertion loss.

The webinar will include discussion on these related topics:

  • Basics of RF transmission line circuitry.
  • Overview of the RF properties of a simple PTH via.
  • Variables associated with obtaining accurate impedance measurements.
  • Test vehicle details.
  • Signal launch experiments.
  • Measured RF data showing different PTH via designs for transitioning a signal trace between inner copper layers of a multilayer PCB.
  • Reporting on several different, measured PTH via designs that transitioned a signal trace to different copper layers resulting in improved bandwidth and signal integrity.

About the presenter: John Coonrod is Technical Marketing Manager with Rogers Corp.’s Advanced Connectivity Solutions, based in Chandler, Arizona. He has been involved in the PCB industry for almost 30 years. A frequent presenter and author of the “ROG Blog” hosted at, he is Vice Chair on the IPC D24C High Frequency Task Group. He holds a BS degree in Electrical Engineering from Arizona State University.