FR2 and FR4 are different types of printed circuit board (PCB) materials that are commonly used in electronics manufacturing. The main differences between the two types of PCBs are their material properties and the applications for which they are most suitable.

FR2 PCB: - FR2, or Fire Retardant 2, is a type of PCB material that is made from phenolic resin and cotton paper. - It has a relatively low cost and is commonly used for single-sided and double-sided PCBs in low-cost consumer electronics, such as toys, calculators, and remote controls. - FR2 PCBs have a lower thermal resistance and are not suitable for high-power or high-temperature applications.

FR4 PCB: - FR4 is a type of PCB material that is made from woven fiberglass cloth and epoxy resin. - It has a higher cost compared to FR2, but it offers better electrical insulation, higher mechanical strength, and higher thermal resistance. - FR4 PCBs are commonly used for multi-layer PCBs, high-frequency applications, high-power applications, and applications that require high reliability and performance, such as in telecommunications, automotive, aerospace, and industrial electronics.

In summary, FR2 PCBs are suitable for low-cost, low-power applications, while FR4 PCBs are suitable for high-performance, high-reliability applications.