PCBMASTER Helps You Understand - Rogers RO4350B

Author: Jack Wang

Rogers RO4350B is one of the most popular RF PCB materials currently. It is a hydrocarbon/ceramic laminate with a dielectric constant of 3.48, which is highly suitable for the requirements of printed circuit boards by commercial equipment manufacturers.

RO4350B is a patented material composed of hydrocarbon resin, glass cloth, and ceramic filler. Its electrical properties are close to those of polytetrafluoroethylene (PTFE)/glass cloth materials, but its processing performance is as simple as that of epoxy resin/glass cloth materials. This means you can process it with standard FR-4 processing techniques, and the cost is much lower than that of traditional microwave materials. Most importantly, it does not require complex drilling or special processing procedures like PTFE PCBs.

Core Advantages of RO4350B PCB

1. Low RF Loss: In high - frequency applications, signal loss is extremely small.

2. Stable Dielectric Constant: The dielectric constant changes very little with temperature, resulting in more reliable performance.

3. Low Thermal Expansion Coefficient: It has a low thermal expansion coefficient in both the z - axis and on the board surface, making it suitable for high - precision applications.

4. Small Dielectric Constant Tolerance: The dielectric constant is precisely controlled, making it suitable for designs with strict performance requirements.

5. Frequency Stability: The electrical properties remain consistent at different frequencies.

6. Compatible with FR-4: It can be easily mixed with FR-4 materials, which is suitable for multi - layer board designs and offers high cost - effectiveness.

Typical Applications of RO4350B PCB

· Cellular base station antennas and power amplifiers

· Microwave point - to - point connections (P2P)

· Automotive radars and sensors

· Radio - frequency identification (RFID) tags

· Real - time satellite LNB

How to Select High - Frequency PCB Materials?

For high - frequency circuit design engineers, choosing the right PCB material is a technical task. Each material has its own advantages and disadvantages. The key is to check whether its dielectric constant (DK) and frequency characteristics meet your design requirements. DK not only affects the operating frequency of the circuit but also determines the width of the transmission line - the smaller the DK, the larger the line width.

In addition, DK is not a fixed value. It has a great relationship with the roughness of the copper foil in the PCB material. The rougher the surface of the copper foil, the larger the actual DK value. Therefore, the influence of the copper foil must be considered when selecting materials.

RO4350B is a low - loss material composed of hydrocarbon resin and ceramic filler, with excellent high - frequency performance (usually suitable for applications below 30GHz). Its processing technology is similar to that of FR-4, and the cost is low, offering high cost - effectiveness. If you need a low - loss high - frequency PCB material, RO4350B is a good choice.

Matching Materials

RO4350B is usually used together with RO4450F prepreg (PP sheet). The specific DK value can be accurately calculated through Rogers' impedance calculation tool.

 Author: Jack Wang