What is the difference between RO4350B PCB and RO4835 PCB?

Both RO4350b PCB and RO4835 PCB belong to Rogers 4000 series PCB and belong to civil products. Ro4000 series is a kind of laminated material of hydrocarbon resin and ceramic materials. It has the ability of compatible with FR4 mixed pressing, FR-4 processing technology and lead-free welding process. It ensures that PCB processing plant only needs to have lower processing capacity and reduce PCB processing cost, while its low loss (DF) is 0 0037@10GHz ??The temperature stability of dielectric constant is better (50 ppm / °) C@-50 °C to Compared with the traditional PTFE material, the heat treatment capacity is better (heat dissipation coefficient is 0.6w/m / ° K), and the z-axis thermal expansion coefficient (31 ppm / ° C) improves the reliability of through-hole, which can ensure the excellent electrical performance of radar front-end and antenna at 24GHz. Moreover, it belongs to UL 94V-0 flame retardant material, which further contributes to the safety of radar system.

 

The biggest difference between the two is that the antioxidant added to RO4835 is 10 times higher than that of the traditional thermosetting materials, and it meets the requirements of ipc-4103 (high speed and high frequency substrate specification). Rogers radiofrequency board RO4835 was added with anti-oxidation material, and its oxidation resistance was stronger than that of RO4350B. In addition to the difference between DK and DF, the temperature characteristics of DK are relatively poor for products with glass cloth, and the requirements for the temperature range of products become higher. When the coefficient of thermal expansion becomes poor, especially the z-axis, the number of relative layers of the product will decrease. The phase characteristic of high frequency is relatively poor, so it is better to avoid using products with strict requirements on phase. The advantage is that the dimensional stability, hardness and water absorption of the product are relatively good.

 

The working frequency of 24g security radar system is 24-24.25ghz, with a total working bandwidth of 250MHz. FMCW waveform is used to work. Due to the characteristics of high frequency and short wavelength, the RF front-end and antenna of the radar system can only use high-frequency microwave materials. However, the security industry is full of competition, which makes high-frequency microwave materials not only need good performance, but also suitable price In other words, high-frequency microwave materials with high cost performance are needed.

 

Rogers, an internationally famous manufacturer and R & D manufacturer of high-frequency microwave materials, focuses on introducing two kinds of high-frequency microwave PCB materials: RO4350B hydrocarbon ceramic and RO4835 hydrocarbon ceramic, aiming at the 24g security radar market and different application scenarios.