Having issues with series resistive and reactive impedance of the coil

Thread Starter


Joined Dec 31, 2011
Good day everyone, this is my first post!

I thought I'd try and see if someone can help me dig into this circuit a bit and figure out why and how the selected inductor/capacitor matches were selected.
I noticed the two frequencies selected are around 900mhz and 2.2ghz. As well as the diodes have an internal capacitance of 0.18pF each at the operating conditions in the picture below. (3uA, 25ohms)

For the life of me I can't figure out how the 2 coils and capacitors were selected.
Even plugging in the angular frequency of 1/sqrt(Cc*Coil) wouldn't yield the proper frequency. The angular f formula for the 900mhz portion (39nH, 2.7pF) only yields roughly 490mhz for me.