Regarding peripheral circuit constants of LT5560

Hi.

I am an RF engineer, I think the purpose of this components is to compensate imaginary part of impedance, because the the input (or output) has got not only real impedance but also imaginary part, it needs to be compensate in next matching stage. The formula for LC-balun considers only real part of impedance.
Input capacitor can be excluded from matching - only DC blocker. Similar to output inductance 270nH, the purpose is bias of OUT-. The impedance at 140MHz is quite high (~240Ohm).

Hi.

I am an RF engineer, I think the purpose of this components is to compensate imaginary part of impedance, because the the input (or output) has got not only real impedance but also imaginary part, it needs to be compensate in next matching stage. The formula for LC-balun considers only real part of impedance.
Input capacitor can be excluded from matching - only DC blocker. Similar to output inductance 270nH, the purpose is bias of OUT-. The impedance at 140MHz is quite high (~240Ohm).