how to use a 3-port transformer in ADS

[yzriver]

Hi, I have a question in how to use a 3-port transformer to match the differential device.

for example, a in the picture, the input impedance is 50ohm, the two load is 200ohm. Is the turn ratio T1=T2=0.5? I can't get a good return loss. how to select the turn ratio in this example to have a good matching?

thank you,

Jay

 

[shlomo22]

More turns -> more voltage less current -> more impedance.

You have more impedance at the output than the input, so you need turn ratio>1, i.e. T1=T2=sqrt(R0/Z0) not what you wrote.