About the Balun application!

[gdhp]

Hi

I use the balun to transfer the single signal to two differential signals. But i met a problemn.

When i input a 1M sinewave, the differential signals are ok.

When the input signal frequency increase to beyond 5M, the output differential signals are almost the same, not differential.

Another, when the input frequency increases, the energy loss is very worsen.

What is the problemn? The 50ohm impedance is ok.

Who can tell me what is the root cause?

Thx

 

[SamuraiNeophyte]

Your balun isn't a broad band balun? It is designed for 1MHz, but rulls off slowly to 5MHz? Therefore it isn't a balun at those frequencies and therefore not efficient either. Probably putting all the signal into one of the differential outputs losing 3dB? How are you measuring the differential impedance?

Baluns are kind of a magical device and they can be very touchy.