coolsummer
Junior Member level 3
Hello,I'm designing a VCO over 70GHz,and I used 1/4 wavelength transmission line to act as impedance-transformer:at one terminal of the transmission line it is shorted , so it is high-impedance looking from the other terminal.I put a capacitance at the terminal of the line to make it shorted in high frequency.
But in high freq. ,the impedance of bonding wire should be taking into account, on-chip gnd is connected to the real gnd through inductor, that is to say on-chip gnd is not real gnd,so the terminal of the transmission line is not truly shorted,it could not actually act as 1/4 wavelength-shorted transmission line...am I right? I'm confused about it for a few days...
But in high freq. ,the impedance of bonding wire should be taking into account, on-chip gnd is connected to the real gnd through inductor, that is to say on-chip gnd is not real gnd,so the terminal of the transmission line is not truly shorted,it could not actually act as 1/4 wavelength-shorted transmission line...am I right? I'm confused about it for a few days...