A discussion topic between designers, namely those who only do circuit design and have no interest in the field of EMC, and compliance engineers attempting to meet regulatory compliance requirements, is the use of FR-4 as the core material for printed circuit board construction. Fiberglass Resin (FR) is low cost and has been used in almost every electrical product for decades, with exceptions such as military and satellite applications, harsh environmental conditions, and other unique uses. The disagreement lies with the extent that we can use FR-4 in high frequency applications and should we be concerned more with electrical performance or manufacturing and assembly.
