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Reversing pins on a Balun

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Hawaslsh

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Hello,

Pinouts.png


I had a question concerning the use of a balun and if it was possible to reverse the pinout suggested by its datasheet. I am planning on using a very nice, wideband mixer (LTC5552) and its IF output is differential. I already have a balun made by Macom (MABA-011082) I was thinking of using on the mixers IF output. The pinout for both devices is above. However, when I was looking at the possible layout for a PCB the suggested pinout from the balun crisscrosses the IF output from the mixer (left picture below). I realize I can rotate he part and route a line underneath the balun itself. But that wouldn't be the best transmission line geometry in my opinion and matching the phase exactly would be a bit harder (right picture below).
CrissCrossed Layout.png
Rotated part.PNG

Sadly I think the asnswer is no, but I wanted to ask others if it was possible to "reverse" the suggested balun pinout and still maintain the same operation / performance (picture below). Instead of using the dots on the primary and secondary coil as the positive end, I was thinking of using the non-dot end as the positive, and ground the primary dot, Any thoughts?
New Pinout.png

Thanks in advance,
Sami
 

Hey Sami,

You can always interchange IF+ and IF-. They are just out of phase with each other. There is nothing like +ve and -ve here.

In that case, your routing becomes the simplest you can think of!
 

    Hawaslsh

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Yes, but not pin 1 and 2 of the unbalanced BALUN port as indicated in your schematic.
You can always interchange IF+ and IF-.
Thank all!
I will simply change the IF ports in the schematic and leave the Single ended side as recommended.
Best option.PNG
 

You can interchange the Differential Pins, doesn't care.
But take care the symmetry so connect the differential pins symmetrically on the layout so that tracks may have equal length.
 

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