The Rog Blog is contributed by John Coonrod and various other experts from Rogers Corporation, providing technical advice and information about RF/microwave materials.
December 11, 2013
Achieving reliability and high performance from a PCB material is not simply about selecting the optimum dielectric material for an application—the copper on that material also plays a critical role. The quality of the copper on a PCB, including its surface roughness, and how the copper is joined with the dielectric material, can go a long way towards determining the performance possible with that PCB material, particularly at RF and microwave frequencies.Read More
November 15, 2013
Choosing a printed-circuit-board (PCB) material is a critical step in the design of any new RF/microwave circuit, since the material’s characteristics will ultimately determine the performance and capabilities of the circuit. Picking an electronic-design-automation (EDA) software package to model any new design can go a long way towards improving the design experience (and the levels of performance possible) since the right software can help predict the performance of circuits fabricated on different PCB materials. Understanding how these EM simulation software tools differ and how they can be applied to model different PCB materials can greatly benefit the design process.
October 17, 2013
Handling high power in an RF/microwave printed-circuit board (PCB) requires not only effective circuit-design techniques, but PCB material capable of “getting the heat out.” High-power handling for a PCB material is synonymous with low loss and higher thermal conductivity. But in choosing a circuit material for high-power applications, such as power amplifiers and power combiners/dividers, many other PCB parameters come into play. This includes the maximum operating temperature (MOT) for a given material, which essentially describes a danger temperature above which performance and reliability problems can be aggravated.Read More
September 25, 2013
Three approaches are commonly used for bonding multiple layers of PTFE-based circuit laminates, such as Rogers RT/duroid® 6000 series and RO3000®series materials. These three approaches rely on thermoplastic films, thermoset prepregs, and direct bonding methods, such as fusion bonding processes. The first two techniques require additional films or prepreg materials which function like glue to keep the multiple layers in one piece. The third approach employs heat and pressure to bond the multiple PTFE-based material layers into one piece.Read More
September 9, 2013
Dielectric constant (Dk) is a key parameter to consider when choosing a microwave printed-circuit board (PCB). But what microwave circuit designers may not always appreciate is the “choice within a choice” with some PCB materials, or when it might make sense to select a circuit material with a higher Dk value. High-Dk circuit materials can make it possible to miniaturize high-frequency circuits beyond what is possible with lower-Dk circuit materials. Understanding where high-Dk circuit materials fit within an RF/microwave designer’s toolkit can provide engineers with a great deal of flexibility when developing both active and passive high-frequency circuits.Read More
August 21, 2013
Dissipation factor, also known as loss tangent, is a printed-circuit-board (PCB) material parameter probably often overlooked when engineers size up their possible choices for PCB materials. But it is a parameter that can tell a great deal about how a material will perform in different applications and environments. And it is a PCB parameter that is certainly worth spending a little time to get to know better.Read More
May 3, 2013
Achieving high reliability for a high-frequency circuit or system starts with the printed circuit board (PCB). The PCB material must deliver consistent performance over time and changing conditions, such as temperature. As explained in the previous Blog (part one of this two-part series), it is possible to spot PCB materials that are “built to last” by assessing a number of their key performance parameters, such as coefficient of thermal expansion (CTE). In fact, PCB materials such as Rogers RO4835™ laminates can be engineered for high reliability through a careful combination of material components resulting in specific performance characteristics.Read More
April 16, 2013
High reliability is a goal and desire for all designers and end-users of high-frequency printed-circuit boards (PCBs). Since all of the components mounted on the PCB depend on it, it is expected to deliver dependable and consistent performance over time. But depending on the operating conditions, it can sometimes be difficult to achieve. In an attempt to help, the next two Blogs will explore PCB material reliability: this blog, Part 1, will review some of the general obstacles for a PCB material to achieve good long-term reliability while the next blog, Part 2, will take a close look at how the characteristics of one particular PCB material add up to good long-term reliability.Read More
50th ROG blog posting
April 1, 2013
This ROG Blog series on printed-circuit-board (PCB) materials from Rogers Corp. (www.rogerscorp.com) has reached the half-century mark, already covering a wide range of topics on circuit materials with this, the 50th ROG Blog. It has even detailed the effects of different PCB material thicknesses on circuit performance, and described the influence of conductor roughness on circuit performance. While it would be difficult to pick out the top 10 Blogs from the first 49 Blogs appearing since August 2010, at least 10 of these ROG Blogs deserve mention for how they have attempted to help readers with their different uses of PCB materials.