Archive for the ‘RF Board’ Category

What’s RF PCB board?

Tuesday, November 23rd, 2021

You may have ever heard of RF PCB, but do you know what it is and What are the characteristics of these kinds PCB?

Today let us make a simple introduction for it.

RF PCB, means radio frequency PCB. People also called these PCB High frequency PCB, it is for the PCB with a higher electromagnetic frequency, and it is used on the products field with high frequency. (Frequency greater than 300MHZ or wavelength less than 1 meter) and microwave (frequency greater than 3GHZ or wavelength less than 0.1 meter). It is made by microwave substrate with common PCB manufacturing process or with some special way to make.

High-frequency boards have very high requirements for various physical properties, accuracy, and technical parameters, and are often used in communication systems, automobile anti-collision systems, satellite systems, radio systems and other fields.

How can we know which PCB materials are suitable for making the RF boards?

When evaluating the high-frequency characteristics of a substrate material, the key to its investigation is the change in its DF value (Dissipation Factor).

For substrate materials with high-speed and high-frequency characteristics, in terms of changing characteristics at high frequencies, there are two distinct types of general substrate materials: one is that with the change of frequency, its (DF) value changes very little. There is another type that is similar to the general substrate material in the range of change, but its own (DF) value is lower.

The common epoxy resin-glass fiber cloth-based materials (FR4), the DK value at the frequency of 1MHz is 4.7 and the change of the DK value at the frequency of 1GHz is 4.19. Above 1GHz, the change trend of its DK value is gentle. The change trend is that as the frequency increases, it becomes smaller (but the change is not large). For example, at l0GHz, the DK value of FR-4 is generally 4.15. The substrate material with high-speed and high-frequency characteristics changes in frequency. When the DK value changes slightly, the DK value keeps changing in the range of 0.02 when the frequency changes from 1MHz to 1GHz. Its DK value tends to decrease slightly under different frequency conditions from low to high.

On the other hand, the thermal expansion coefficient of the high-frequency circuit board substrate and the copper foil must be the same. If they are inconsistent, it will cause the copper foil to separate during the cold and hot changes. Secondly, in a humid environment, the water absorption rate must be low, and high water absorption rate will cause dielectric constant and dielectric loss when wet. In general, the heat resistance, chemical resistance, impact resistance, and peel resistance of the high-frequency sheet must be good.

The following are several commonly used high-frequency and high-speed PCB boards we have summarized:

Rogers: RO4003, RO3003, RO4350, RO5880, etc.

TUC: Tuc862, 872SLK, 883, 933, etc.

Panasonic: Megtron4, Megtron6, etc.

Isola: FR408HR, IS620, IS680, etc.

Nelco: N4000-13, N4000-13EPSI, etc.

Other materials like ARLON, Teflon, Taconic are also good for the manufacturing of RF PCB boards.

If you have any question for RF pcb, welcome to send your request and question to discuss more.

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What’s RT/duriod 5880?

Tuesday, December 1st, 2020

For PCB materials, you may have ever heard about many different kinds of materials such as the materials of FR4, Aluminum, Copper base and ceramic base.

But do you know what the duriod 5880 materials is?

Actually duriod 5880 is a kind of materials of the Rogers, it is the materials which is used for high frequency circuit board. RT 5880, which is famous for its low dielectric loss, low moisture absorption, and stable dielectric constant. The PCB made of duriod 5880 can be widely used in airborne and ground-based radar systems, millimeter wave applications, and space satellite transceivers.
Different with other kinds materials, the color of the RT 5880 materials is black.

Why this material can be used in such high end field? Let’s see below to know more information.

Excellent dielectric properties:
RT/duroid 5870/5880, as a new generation of high-frequency laminate, is made of polytetrafluoroethylene composite material (PTFE). At the same time, glass microfibers are randomly distributed in the material, which provides the greatest strength during the production and application of the circuit board.

High-frequency circuit design has strict requirements on the dielectric constant of the printed circuit board. RT/duroid 5880 has an ultra-low dielectric constant and remains the same in a very wide operating frequency range.

At 10GHz operating frequency, the measured dielectric constant is only 2.33/2.2, which is significantly lower than similar materials on the market. Therefore, from the perspective of performance parameters and production costs, the board is more suitable for high-frequency application design than similar products.

At the same time, under the same standard (f=10GHz), and the dielectric loss of the RT5880 is only 0.0012/0.0009. The extremely low dielectric loss makes it very suitable for high-frequency and the field of wide-band applications which requiring minimal dispersion and low loss.

In addition, the extremely low moisture absorption rate makes it an ideal choice for applications in high humidity environments. The moisture absorption rate of RT/duroid 5880 is only 0.02%, so it can meet the strict requirements of mechanical reliability and electrical stability in the complex microwave structure design, and it is also suitable for applications in high humidity environments.

With the continuous improvement of the operating frequency of high-frequency circuits, the requirements for the dielectric constant and dielectric loss of the circuit board are becoming more and more stringent. The excellent performance of RT/duroid 5880 in these two aspects can significantly improve the design of high-frequency circuits. Definity, improve circuit performance.

Easy to process and install
In this high-frequency design, in order to meet the requirements of electromagnetic shielding and compact design, printed circuit boards are often installed in various irregularly shaped cavity structures. Therefore, the PCB board must be designed in different shapes and suitable for production and Installation.

For RT/duroid 5880 laminate, which is easy to cut, trim and good for PCB manufacturing.

At the same time, it can resist all the solutions and chemical agents used in the process of etching and plating through holes, and it has a good performance of the cold and heat resistance.

The composite material RT/duroid 5880 can be covered with a laminated copper foil for some key electrical applications, and brass plates or copper can also be used as required.
Usually laminates of the RT/Duriod 5880, it can make double-sided copper clad with thicknesses ranging from 1/2 oz. to 2 oz./ft2 (8.5~70 μm) to meet most custome’s requirements for the thickness of copper foil.

Our company has focus on the PCB fabricationi for more than 15 years, we can make PCB with Rogers PCB with RT/Duriod 5880, as well as RO4003C and RO4350B with different thickness.
If you are interesting to know more and your PCB also want to made of RT/Duriod 5880, please feel freely to contact us for more information related.

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