1. FMAT7620-20 Substitution Conclusion From the perspective of key electrical parameters and mechanical compatibility, the FMAT7620-20 can fully replace the original SA3R-20 part, offering even superior performance coverage. Both devices share identical specifications for attenuation value (20dB), power handling (2W), impedance (50Ω), and package form (SMA In-Line Module), ensuring direct compatibility in basic functionality and physical interfacing. The core difference lies in the frequency range: the SA3R-20 supports 0–3 GHz, whereas the FMAT7620-20 extends to 0–18 GHz. This means the substitute part is capable of operating in higher frequency bands. Furthermore, within the original 0–3 GHz application range, the FMAT7620-20 may offer improved frequency response flatness and stability—a likely benefit of the tighter precision control typically required for high-frequency design. The substitution is not only feasible but also provides additional assurance for potential high-frequency requirements or performance headroom in the system.