By Mark Thompson | Published on: September 23, 2013
In this short post I will talk about broadside coupled impedance structures.
A broadside coupled impedance structure is one where the signal or signals reference one another in the PCB Z axis between two reference planes. This differs from a “dual strip-line” type structure where the two signal layers are routed 90 degrees to one another. To minimize the cross section of trace coupling here, the traces are DIRECTLY above and below one another to INTENTIONALLY couple. The stack up for these type structures must place the two signals on either side of a single core to minimize any trace offset. If placed on two separate cores, any registration movement in lamination could create an unwanted trace offset resulting in irregular coupling. If as mentioned before the two signals reside on either side of a single cured core, the movement layer to layer would be minimal through the lamination process.
Copyright © 2013 Prototron Circuits, Inc. All Rights Reserved.