hi Ankit
welcome to the forums
you are going to have to be a bit more specific as far as the circuit goes so we can suggest something practical
show us some diagrams, Which RFIC etc ???
A BALUN is a mix of 2 words BALanced and UNbalanced, meaning its used to match a balanced antenna, for example, to an unbalanced feedline like coax cable
If a BALUN isnt used, a problem of RF currents can flow on the screen ( shield ) of the cable and get radiated causing problems to surrounding equipment.
Within equipment, say a transmitter or receiver, BALUNS may occassionally be used to match different impedances between stages. That is also done between feedlines and antennas. These style of BALUNs are called impedance transformers.
An example is a folded dipole antenna has 300 Ohm impedance but the coax cable is only 75 Ohm impedance. so we use a 4 to 1 (4:1 ) ratio BALUN transformer
cheers
Dave
