RF Design Solutions

[Atif Hussain Shah]

Will 1:1 Balun give a 3dB gain at output when the input is a differential signal?
The differential impedance is 50 ohm and single ended impedance is also 50ohm

 

[BigBoss]

BalUns don't provide Gain, instead they have losses..

 

[Atif Hussain Shah]

BalUns don't provide Gain, instead they have losses..

But when balun is used for converting differential signal to single ended signal, 3dB gain is achieved at output

 

[FvM]

How do you derive this? RF signals are usually measured as power, e.g. in dBm. A lossless balun can have at best output power equal input power. In case of 1:1 balun, this corresponds to equal in- and output voltage.

 

[Atif Hussain Shah]

How do you derive this? RF signals are usually measured as power, e.g. in dBm. A lossless balun can have at best output power equal input power. In case of 1:1 balun, this corresponds to equal in- and output voltage.

Yes in case of 1:1 balun the output power will be equal to input power
But in case of 1:2 balun what will be the output power.
Basically i want to ask/confirm that as Balun has conversion loss and for 1:2 balun the conversion loss will be 3dB less than for 1:1 Balun

 

[FvM]

Ouput power is always input power minus losses. Voltages are different depending on the impedance ratio.