sirricky
Newbie level 6
I designed an onchip balun to fullfill the single to differential convertion at output. the self-inductor was about 0.3nH. and the operating freq. was about 18G. the balun differntial output had a center tap, which should be connected to a AC ground. I found that if the center tap was not connected to an ideal gnd, for example, connected to a 200pH inductor as a paracitics, the balun's output becomes imbalance, and the imbalance was greatly related to the center tap connection. Anyone came across this problem?