Balun design, is it possible with less than 2 inductors / 2 capacitors?

Hello guys,

The classical lattice type balun requires a LC and CL path such that it creates +90 degrees shift and -90 degrees shift.
However, there are some designs that I've come across that are using less than 2 Ls and 2 Cs.

For example,

it shows a Ca-La-Cb, where RFIN takes input between Ca-La, RFINB takes input between La-Cb.
I don"t quite understand how this is possible.

Another similar (but different) one is from SiLabs

If anyone has any literature on how this kind of balun works, it would be great to learn!

Thanks!

As mentioned in the Analog datasheet, the CLC circuit can't achieve symmetrical matching. So it's effective unsuitable for differential transmitters. The Silabs circuit looks like a LC-CL balun with slightly different topology.