M565: RF Balun Transformers

This application note is designed to help the reader understand how balun transformers can be used in today's RF/Microwave communication applications. There is an increasing demand for balun transformers in today's telecommunication market and M/A-COM is leading the field with this device. As many as six of this device can be used around any particular chip as illustrated in figure 4. M/A-COM's balun transformer can be classified into two groups A) The flux coupled balun transformer and B) The transmission line balun transformer. Insertion Loss (dB): Loss due to transmission from primary dot port to secondary dot port and secondary port. Most balun transformers are symmetrical through their central horizontal axis, therefore, an input can be applied at the primary dot port or the primary port with differential outputs at the secondary dot and secondary ports. Amplitude Balance (dB): Measure of the difference in amplitude between the two differential outputs. Phase Balance (degrees): Measure of the difference in phase between the two differential outputs, i.e. measured from ±180°.