Hello,
I want to use LMX2594 RF output ports in single ended form. I have seen from evaluation board that, one of the differential pair is terminated with 50 ohm load, even though a pull-up 50 ohm resistor is used on board.
For example let us say I want to use RFoutAP output for the single-ended application. It is suggested that to terminate RFoutAM with 50 ohm. There are already seperate 50 ohms soldered on board.
Assuming capacitance are for DC block and have little to no impact in matching, each differential (RFoutAP,RFoutAM etc.) sees 25 ohms to ground. So the impedance between, RFoutAP and RFoutAM should be 50 ohms in total which I did not expect because I thought they should be 100 ohms.
So what is the characteristic impedance between differential RF pairs ? I just want to use one of the outputs in single ended mode, so it is critical for me how to make this application correctly, which is different from the evaluation board.
TL;DR : Are the characteristic matched impedance between differential RF output pairs are 50 ohm instead of 100 ohm ?
Best Regards,
