ROG Blog

The Rog Blog is contributed by John Coonrod and various other experts from Rogers Corporation, providing technical advice and information about RF/microwave materials.

Minimize Microstrip Radiation Effects

Radiation loss can be a concern in microstrip circuits at higher microwave frequencies. Fortunately, its effect can be minimized by reducing the number of discontinuities in a circuit design, and by carefully weighing the choice of circuit substrate material in terms of thickness and dielectric constant, where thinner materials and higher dielectric constants can both contribute to lower radiation losses.
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Low-Loss PCBs Enable MM-Wave Auto Electronics

Evolution of the electronic systems in automobiles and other vehicles is exciting to watch, and many technologies once associated with the military, such as radar systems, are becoming available to average drivers. As highlighted in the previous ROG blog, 24-GHz short-range-radar (SRR) systems are being offered more and more in car models around the world. But vehicle designers and manufacturers are also looking ahead to the greater resolution possible with 77- and 79-GHz automotive radar systems. And for that evolution in automotive electronic systems to truly take place, printed-circuit-board (PCB) materials are important building blocks that will enable the potentially much safer automobiles of the future.
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PCB Advances Drive Automotive Applications

Automotive electronic circuits were once as simple as switches for headlights and windshield wipers. But modern automobiles take advantage of electronic circuit technology more than ever, often working with high-frequency signals at RF, microwave, and even millimeter-wave frequencies. For consumers, these advanced systems promise greater safety and an enhanced driving experience. For the manufacturers of these systems, these automotive applications offer the potential of bringing high-frequency technologies to millions of users. And to suppliers of printed-circuit-board (PCB) materials, such as Rogers Corporation, these emerging applications pose challenges of providing high-performance reliable circuit materials at acceptable prices that help fuel mass-market applications.
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PCB Considerations For Defected Structures

As strange as it may sound, the use of circuit defects is a growing trend in high-frequency circuit design, especially for passive circuits such as filters. More precisely, the trend is in the increased use of defected ground structures (DGSs) and defected microstrip structures (DMSs) to alter the responses of microstrip circuit designs. Just what are these DGS and DMS forms, and does incorporating them into a high-frequency circuit change the way the PCB material should be specified?
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Learning To Launch Onto Different Circuit Thicknesses

The transition, from a waveguide or coaxial connector to the PCB, is critical to the performance of the circuit, and the PCB’s thickness can impact how an end launch transition is made. Waveguide and coaxial connectors come in many shapes and sizes, as do PCB thicknesses, and matching the connector to the substrate thickness can play a large role in the overall performance and reliability of that design.
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Matching Materials To Millimeter-Wave Circuits

Millimeter-wave frequencies offer great potential for transferring wide-bandwidth, high-data-rate signals. But handling signals at these frequencies with minimal distortion requires the right printed-circuit-board (PCB) material, along with an understanding of how to apply that material to the requirements of circuits in the millimeter-wave frequency range. Processing signals from 30 to 300 GHz—the classic millimeter-wave frequency range—presents a unique set of challenges, and choosing the right PCB material can go a long way towards helping to meet those challenges.

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Happy National Engineers Week

Every year, February brings us a reason to celebrate: National Engineers Week.  It’s the one week each year when we take a look at how engineering has changed the world we live in.  This year’s theme is Seven billion people.  Seven billion dreams.  Seven billion chances for engineers to turn dreams into reality.
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Picking Prepregs For Peak Performance

Multilayer printed-circuit boards (PCBs) have gained in popularity as designers seek to shrink their circuits. They offer the opportunity to stack a wide range of functions on one multilayer design, even combine analog, digital, and microwave circuits on a single circuit assembly. Designers have learned how to stack laminates with different relative dielectric constants, such as PTFE-based laminates and FR-4, in compact multilayer circuits, but creating such circuits requires careful planning and a good understanding of the role that bonding films and prepregs play in multilayer circuits.
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Digging Out The Details On Embedded Capacitance

Capacitance is a part of every circuit design, whether intended or not. Chip capacitors are available in a wide range of sizes for every function from blocking DC to filtering microwave signals. But as small as they are, chip capacitors still occupy valuable area on a printed-circuit board (PCB), and mounting them—even by machine—can be labor intensive and time-consuming. For these and several other reasons, a method for fabricating PCBs with embedded capacitance provides a way to simplify and miniaturize some circuit designs. But is it right for your design?
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Choosing A Laminate That Matches The Model

Choosing a substrate material for use as the printed-circuit board (PCB) in a new design can be a stressful experience, unless it is a matter of sticking with that “tried-and-true” material that has worked so well in the past. But with ever-evolving and improving dielectric and laminate materials, and increasing demands to achieve high performance levels at reduced costs, most design engineers are wise to consider the cost-versus-performance benefits of different types of commercial PCB materials. Previous blogs have detailed how selecting a PCB material can be influenced by different performance requirements. This blog will explore the role that a computer-aided-design software tool plays in choosing the most suitable PCB material.

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