Microwave Tech - Rogers RO4003C and Rogers RO4350B

Rogers RO4003C and Rogers RO4350B parameters do not know which one is better? Today, ipcb introduces in detail the parameters of high frequency PCB Rogers RO4003C and Rogers RO4350B.

For high frequency PCB design engineers, there are more choices of high frequency PCB materials than ever before. Each high frequency PCB material has its own advantages and disadvantages. It is difficult to select the most appropriate PCB material without carefully comparing various parameters of high frequency PCB material. By comparing the main parameters of Rogers' microwave plate RO4003C and RO4350B, ipcb can help circuit design engineers to know and choose the most suitable board.

Rogers RO4003C and Rogers RO4350B are high frequency laminates with ticertm TCR film resistance layer. The main parameters are shown in the figure below.

high frequency PCB Rogers RO4003C and Rogers RO4350B parameters

When PCB design engineers choose PCB board, the first concern is whether the working frequency of the Board meets the requirements. In addition, the dielectric constant also affects the linewidth of transmission line or matching line. The smaller the DK, the wider the transmission line. The linewidth of materials with different dielectric constants needs to be recalculated or simulated.

RO4003C and RO4350B Dissipation factor DF

Without considering the influence of other factors, the smaller the dissipation factor, the smaller the signal loss in the transmission process. Both RO4003C and RO4350B have very low dissipation factors, and the transmission line loss of ro4350 is larger than that of RO4003C. When the system gain design margin is tight, choosing ro4003 with smaller dissipation factor can reduce the transmission loss of dielectric plate.

Ɛr thermal stability coefficient

The change of temperature will cause the change of dielectric constant. Through theྣr thermal stability coefficient of RO4003C and RO4350B, the dielectric constant of two kinds of plates at a certain temperature can be estimated to judge whether they are in the acceptable range. The lower the absolute value of Ɛr thermal stability coefficient is, the more stable the dielectric constant is in the working temperature range.

RO4003C and Rogers RO4350B Coefficient of thermal expansion

The change of temperature will inevitably lead to the change of the physical size of the plate. For PCB, the copper layer (including through-hole) and dielectric material are pressed together at room temperature. With the change of temperature, copper and medium will change with different thermal expansion coefficient, which will inevitably cause temperature stress. When the temperature stress exceeds the bearing capacity of copper layer, medium or bonding between copper layer and medium, PCB will be damaged. The temperature stress in Z axis may lead to the fracture of metallized through-hole; the repeated stress in X / Y axis may lead to copper layer tearing or loose bonding between copper layer and medium. In the process of plate processing, because of the etching shrinkage (baking after etching), the thermal expansion coefficient is different, which will cause the change of the size of the plate after processing.

The thermal expansion coefficient of copper is about 19ppm / degree Celsius, and the thermal expansion coefficient of RO4003C and RO4350B is similar to that of copper. The values of X / Y / Z axis are 11 / 14 / 46 (PPM / degree Celsius) and 10 / 12 / 32 (PPM / degree Celsius) respectively. In contrast, RO4003C is closer to the thermal expansion coefficient of copper in X / Y axis, and has better dimensional stability in sheet metal processing; r04350b is closer to the thermal expansion coefficient of copper in Z axis, which can better protect metallized via.

RO4003C and RO4350B Water absorption

Water absorption represents the ability of an object to absorb water under normal atmospheric pressure. The higher the water absorption rate is, the higher the proportion of water in the medium is, and the greater the influence on the characteristics of the medium is. In high humidity environment, it is more suitable to select RO4003C plate with low water absorption.

Of course, in the selection of plates, in addition to the above main indicators, we should also consider other performance indicators of plates according to the actual application environment, such as copper foil peeling strength, thermal conductivity, flame retardant grade, lead-free process, cost, etc., and fully understand the actual application environment and the meaning of various parameters of the plate, so as to select the most appropriate plate.

The above is the comparison of high frequency PCB Rogers RO4003C and Rogers RO4350B parameters. If there are other questions, you can consult ipcb. Ipcb specializes in the development and production of various high-end PCB boards, high-precision FPC circuit boards and PCB circuit boards, high frequency and mixed pressure PCB proofing and mass production. The independent patent system can query PCB prices online.