Rogers Corporation is built on the core belief that we have a responsibility to our coworkers, our community, and ourselves to make health, safety, and environmental issues the key considerations in everything we do. We uphold this belief by giving back to the communities around us.
On Sunday, July 13th, the Rogers Golf Classic supporting the Special Olympics of Quinebaug Valley Connecticut was held at the Connecticut National Golf Course in Putnam, Connecticut.
The shotgun start marked Rogers Corporation’s fifth golf classic in honor of the Special Olympics. Since the golf classic’s inception in 2010, we have continuously seen an increase in participation and funds raised.
For 45 years, the Special Olympics has been providing year-round sports training and athletic competition in a variety of Olympic-type sports for children and adults with intellectual disabilities, giving them continuing opportunities to develop physical fitness, demonstrate courage, experience joy and participate in a sharing of gifts, skills and friendship with their families, other Special Olympics athletes and the community.
To participate in the Rogers Golf Classic, each golfer donated $100 and received golf, cart rental, food throughout the day, and 2 drink tickets.
Are you interested in donating to the Special Olympics? Donations can be made here.
Ut oh! We’ve all had minor accidents or occasional drops with our beloved tablet PCs. Ever wonder what keeps your tablet working despite these calamities? Tablet designers around the globe have learned the secret for sealing out dust and protecting tablets from impacts. That’s why they depend on our specially-engineered PORON Urethanes cushioning materials.
It is difficult to protect tablets from impact as they become thinner. The trends toward larger and more expensive screens in thinner devices mean that it is now more important than ever to protect the display.
If you look closely at your tablet display, you may be able to see a thin black line around the display. Thats most likely the gasket that protects the liquid crystal display (LCD) from bumps, bruises, moisture and dust. When created out of the right material, the LCD gasket can absorb and distribute impact energy, which prevents cracks in the display.
By working closely with tablet designers, Rogers has developed a special portfolio of extremely reliable,ultra-thin cushioning materials to meet the demands of these cool new devices. Our PORON Urethane foam materials absorb and distribute impact energy, preventing unwanted cracks in display screens. They not only protect against the first impact but continue to perform over and over again due to their excellent resistance to compression set.
Specially engineered for tablet display protection, PORON ShockSeal foam solves the unique challenges of cushioning, sealing and protection for tablets larger displays. Under stringent test conditions, this innovative material has been shown to reduce impact force for mobile devices by up to four times that of materials typically used for display gaskets.
If you want to see the dramatic difference for yourself, a couple of our bright tech-savvy engineers have created a brief video that demonstrates how this material performs in the typical drop ball test used by many designers.
Our innovative cushioning materials are used for a wide range of impact protection, and some designers take the benefits of our materials to the extreme. G-Form has designed our extreme impact protection cushioning, PORON XRD material into a tablet case so that you can even bring your tablet with you on your extreme sports like mountain climbing and perhaps even sky diving. Who knows where the materials technologies from Rogers Corporation will turn up next?
Read more about our materials for display protection or the wide range of our high performance foams design solutions. Or contact us to discuss your own unique design challenge and how Rogers can be of help.
Power dividers/combiners may be among the most popular and most used of high-frequency components. And couplers, such as directional couplers, are not far behind. These components help to divide, combine, and direct high-frequency energy from antennas and within systems with minimal loss and leakage, and the choice of printed circuit board (PCB) materials for these components can be a strong factor in approaching the ideal performance levels expected from each component. When designing and fabricating power dividers/combiners and couplers, it can be helpful to better understand how different PCB material properties relate to the final performance possible with these components, to help set limits on a number of different performance parameters, such as frequency coverage, operating bandwidth, and power-handling capability.
A wide range of circuits have been developed as power dividers (which serve as power combiners when used in reverse) and couplers, and they are available in many forms. Power dividers can be as simple as two-way dividers or as complex as N-way power dividers, with N a fairly large number as required by a system’s design. Many different directional and other coupler configurations have been developed over the years, including Wilkinson and resistive power dividers and Lange and quadrature hybrid couplers, in many different shapes and sizes. Matching a PCB material to any one of these circuit designs can help in the quest for achieving optimum performance.
These various circuit types offer tradeoffs in construction and performance, to help designers match them to different applications. A Wilkinson two-way power divider, which is designed to provide two output signals with equal amplitude and phase from a single input signal, is essentially a “lossless” circuit, designed to provide a pair of output signals that are each 3-dB less (or one-half the power level) than the input signal (with power dividers having more output ports suffering more loss per output port as a function of the number of outputs). In contrast, a resistive two-way power divider may provide a pair of output signals that are each 6 dB less than the power level of the input signal. The additional resistance in the signal path, while it adds loss, also adds isolation between the two signal paths.
The previous ROG blog offered guidance on selecting PCB materials for high-frequency circuits with coupled features and much of that advice can be applied to any search for circuit materials for power dividers/combiners and couplers. As with many circuit designs, the dielectric constant (Dk) is often a starting point when surveying different PCB materials, and designers of power dividers/combiners and couplers generally tend towards using circuit materials with higher Dk values, since those materials support efficient coupling of electromagnetic (EM) energy using smaller circuit features than materials with lower Dk values. A problem with higher-Dk circuit materials, as the earlier blog explained, is the tendency towards anisotropic Dk characteristics across a circuit board, or having different Dk values in the x, y, and z axes of the circuit board material. Wide variations in Dk, also within one axis of the material, can make it difficult to achieve transmission lines with consistent impedance.
Maintaining consistent impedance is critical to achieving high performance in power dividers/combiners and couplers, where variations in Dk (and impedance) can result in uneven distributions of EM energy and uneven power distributions. Fortunately, as noted in the previous blog for circuits with coupled features, commercial PCB materials with excellent isotropic behavior are available for these types of applications, such as the TMM® 10i circuit materials from Rogers Corp. These materials exhibit a relatively high Dk value of 9.8 and the value is consistent within +/-0.245 of 9.8 for all three axes of the circuit material (as measured at 10 GHz). This translates into consistent impedance for the transmission lines of power dividers/combiners and couplers, resulting in consistent and predictably distribution of EM energy in these component. For a PCB material with even higher Dk value, TMM 13i laminate has a Dk value of 12.85 which remains within +/-0.35 of that value (at 10 GHz) for all three axes. In fact, for those interested in reviewing the chief material parameters to consider when impedance matching is of prime importance (for low VSWR performance), an earlier blog highlighted those key materials, using the RO3010™ and RO3035™ circuit materials from Rogers Corp. as examples.
Of course, consistent Dk and impedance is only one PCB material parameter to consider when designing power dividers/combiners and couplers. Minimizing insertion loss is usually an important goal when designing any power divider/combiner or coupler circuit. Ideally, a two-way Wilkinson power divider would provide two output ports each 3-dB or one-half the power level of the EM energy applied to the input port. In reality, every power divider/combiner circuit (and coupler) will suffer some amount of insertion loss, usually depending upon frequency (with loss increasing as frequency increases), and a consideration for a PCB material for a power divider/combiner is how to manage or, hopefully, minimize, the insertion loss of the circuit.
The insertion loss in a passive high-frequency component, such as a power divider/combiner or coupler, is actually the sum of a number of separate losses, including dielectric loss, conductor loss, radiation loss, and leakage loss. While some of these losses can be controlled through careful circuit design, they may also be dependent upon the capabilities of the PCB material and can be minimized through thoughtful selection of PCB material. Leakage loss is minimized in PCB materials from Rogers Corp., for example, since the materials are designed with high volume resistivity to provide high isolation with low leakage loss for fabricated transmission lines. Loss can also result from impedance mismatches (VSWR losses), which can be minimized by the choice of PCB materials with consistent Dk characteristics.
Minimizing loss is of particular importance in power combiners/dividers and couplers that are intended to handle higher power levels, since losses at higher power levels turn to heat that must be dissipated by the component and its PCB material, and that heat can have an effect on the Dk value (and impedance) of the material.
In short, when designing and fabricating high-frequency power dividers/combiners and couplers, the choice of PCB material should be based on a number of different key material properties, including Dk value, consistency of Dk across the material and with environmental factors such as temperature, minimal material losses, including dielectric and conductor losses, and power-handling capability. Starting with PCB material that is matched to the application can help ensure the success of a high-frequency power divider/combiner or coupler design.
Do you have a design or fabrication question? John Coonrod and Joe Davis are available to help. Log in to the Rogers Technology Support Hub and “Ask an Engineer” today.
As the world continues to seek out new sustainable energy sources, as well as more efficient management of traditional sources, power management needs continue to evolve. Today’s wind and solar power alternatives generate large amounts of power and require more flexible and faster controllers. Compact, powerful and reliable methods of managing power are the key, and that’s where power electronics are critical.
With the help of materials and components developed by Rogers Corporation, Power electronics are enabling engineers to use electrical power efficiently and to lower environmental impact sustainably. Power electronics refers to an electrical system that conditions the power of a supply to suit the needs of the load by using fast and controllable solid-state switches known as power semiconductors. Today, devices like Insulated Gate Bipolar Transistors (IGBTs), conduct, block and control electrical energy for a wide array of energy generation, distribution and conversion applications and their use is expected to grow.The IGBT is used primarily as an electronic switch, combining high efficiency and fast switching for a wide array of medium- to high-power applications such as variable frequency power supplies, traction motor control and induction heating. As market demand and power requirements increase, ruggedness and reliability of these devices become even more critical.
At Rogers, we work closely with designers to develop solutions to address their most complex power electronic challenges. At the heart of these semiconductors, we provide substrates that act as interconnections to form an electric circuit (similar to a printed circuit board) and cool the components. Compared to materials used in lower power microelectronics, our substrates must carry higher currents and provide higher voltage isolation (up to several thousand volts) while operating over a wide temperature range (up to 150 or 200C).
Our patented curamik Direct Bond Copper (DBC) Substrates have long been the industry standard for power semiconductor substrates due to their thermal conductivity, excellent electrical insulation and good heat spreading characteristics so critical in power modules. A key advantage of our DBC substrates is their low coefficient of thermal expansion which ensures good thermal cycling performances (up to 50,000 cycles).
We also enable electrical distribution of the electrical current in power electronic modules with our RO-LINX laminated busbars used as key components of IGBTs. Our customized, three-dimensional constructions are utilized in power modules of traction propulsion systems for rail applications, wind and solar inverters, industrial frequency inverters, large UPS systems or power supplies and other applications requiring the distribution of electrical power.
For over 50 years, we have collaborated with designers to develop solutions to enable new devices that can reliably withstand increasingly heavier loads and higher temperatures. Our newest solutions enable designers in worldwide to integrate multiple functions to eliminate manufacturing steps, lower total systems cost, and enable more streamlined packaging. Our RO-LINX PowerCircuit solutions demonstrate our unique ability to understand customers design challenges and provide innovative solutions.
We know that reliability is critical when you’re dealing with power and designers know they can count on Rogers to perform rigorous testing of all of our products to ensure the highest standards in design and manufacturing. As the technology leaders in our industry, our global team of experts partners closely with design engineers to ensure reliability and to understand and develop robust solutions for next generation modules.
Microstrip transmission lines are widely used throughout the high-frequency industry, for both active and passive circuits. They are building blocks for many components, including couplers, filters, resonators, and power dividers/combiners, along with various coupled features formed from microstrip lines that help transfer energy from one point in the circuit to another. Of course, the printed circuit board (PCB) material also plays a major role in how these microstrip transmission lines perform their duties in these RF and microwave circuits, and it can be helpful to understand how certain PCB material characteristics contribute to the ways that microstrip transmission lines and their coupled features perform in these different high-frequency components.
Circuit board materials are selected by designers for a number of reasons, but usually with dielectric constant (Dk) at the top of the list. Maintaining consistent impedance for microstrip lines depends on consistent Dk for a PCB material since a change in PCB Dk at any point in the material will result in a change of impedance for the microstrip transmission lines at that point in the material. Using microstrip coupled features can complicate the choice of circuit materials since such coupled features typically exhibit different, even- and odd-order, wave modes as a function of the PCB material and circuit design. For electric fields between microstrip coupled features, the even-order modes use mainly the thickness or z-axis of the material, while the odd-order modes of the electric fields are mostly in the planar or length-width dimensions (x and y axes) of the PCB material as well as using some z-axis properties.
Ideally, PCB materials would exhibit tightly consistent Dk values in their x, y, and z dimensions, and modern computer-aided-engineering (CAE) software tools typically assume that they do. But in the real world, circuit materials more typically have differences between the Dk value through the thickness (z axis) of the material and the Dk value across the length and width (x and y axes) of the material. PCB materials are referred to as anisotropic in nature when they have different Dk values in the different axes of the material. In contrast, a PCB material with consistent Dk values in all axes is considered isotropic in nature.
Why the differences in Dk values through the material, and what effects can they have on different circuit designs? Most commercial PCB materials are at least slightly anisotropic in nature, due to the composition of those materials. They are formed with dielectric resin materials and some filler material, such as a glass or a ceramic filler, used for reinforcement and attribute adjustments, but which contribute to Dk variations. The manner in which fillers can orient within a substrate during the laminate manufacturing process accounts for the isotropic or anisotropic behavior for some laminates. Other laminates may have glass weave for reinforcement, which can cause Dk variations; the type of glass weave can impact the anisotropic behavior of the laminate. Combining the effects of these potential filler orientation variations with the effects of the glass weave can cause some laminates to exhibit higher variations in Dk in the different axes of the material, making them more anisotropic.
Designers working on microstrip circuits with coupled features often lean towards the use of PCB materials with higher Dk values, since those materials provide more efficient coupling of electric fields than their lower-Dk counterparts. In addition, since circuit dimensions required for a given impedance shrink on PCB materials with higher Dk values, smaller components can be developed with these higher-Dk materials. Unfortunately, the higher-Dk circuit materials also tend to be more anisotropic in nature than lower-Dk circuit materials, adding to the challenge of designing filters, directional couplers, resonators, and other high-frequency circuits based on microstrip transmission lines with coupled features.
PCB materials with high Dk values, typically 10 or more as measured in the z-axis of the circuit material at 10 GHz, can suffer from serious anisotropic characteristics that can challenge even the best of CAE simulation and design software programs. Circuit materials with a high degree of anisotropy may have, for example, a Dk of 10 through the thickness (z-axis) of the material as measured at room temperature and 10 GHz, but the Dk in the x-y plane of the same material may be different by 10% or 15%. When designing a microstrip circuit with coupled features, such as a filter, and using a CAE program, these variations in Dk values can be accounted for as a form of statistical approximation, but specific differences in Dk values, as might occur at a critical microstrip coupled feature, may not be precisely predicted in the CAE program. The variations in Dk typically result in performance variations in the final circuit, which yield differences between performance parameters predicted by a CAE program and performance parameters measured for a prototype with test-and-measurement equipment.
For designers of microstrip circuits with coupled features, variations in PCB material Dk can be detrimental to achieving expected performance results, fortunately commercial PCB materials with high Dk values are available with relatively isotropic natures. For example, the TMM® 10i circuit materials from Rogers Corp. are quite isotropic compared to other circuit materials with Dk value around 10.0. These are ceramic hydrocarbon thermoset polymer composite materials well suited for both microstrip and stripline high-frequency circuits. The TMM 10i circuit materials exhibit a Dk of 9.80 which remains within +/- 0.245 of 9.80 in all three axes of the material. (The Dk measurements are performed at 10 GHz in the z-axis of the material according to IPC-TM-650, method 184.108.40.206.) For designers in need of a PCB material with even higher Dk value, the TMM 13i circuit material offers a Dk of 12.85 +/- 0.35 as measured at 10 GHz in the z axis using the same test method.
These circuit materials are more isotropic than most, with differences of typically 3% or less between the Dk value in the z-axis of the material and the x-y plane of the material. Compare this to the circuit materials noted earlier with differences of 10% or more. In addition to their isotropic natures, the TMM 10i and TMM 13i materials feature coefficients of thermal expansion closely matched to that of copper, supporting production of such circuit features as plated through holes (PTHs) with high reliability.
Of course, CAE design and simulation software continues to advance, and get better at anticipating such variations as found in anisotropic PCB materials. But for some designs, such as those with microstrip transmission lines and coupled features, even small variations in Dk can be disruptive. For designers working with microstrip coupled features and hoping to avoid surprises, the right choice of PCB material can help.
Do you have a design or fabrication question? John Coonrod and Joe Davis are available to help. Log in to the Rogers Technology Support Hub and “Ask an Engineer” today.