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Is there any SMA Connector Model available ?

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SMA connector is specified with typical VSWR of 1.03 at 1 GHZ, I guess it's even better with right semi rigid cable. Residual derivations from ideal connector behavior are probably rather arbitrary or related to wear and thus not reproducible. I don't expect an useful equivalent circuit describing it.
 

pancho_hideboo said:
I mean simulation models such as s-parameter or equivalent circuit.
Click to expand...

The core model would a short piece of 50 ohm line, the parasitics should be very small.

The transition from connector to PCB can introduce parasitics if not done properly, I would expect some series inductance there.
 

I keep my comment in post #4.

The connector is designed to achieve (1 + residual error) VSWR over the specified frequency range. The residual error is caused by production tolerances and deviations from ideal mounting conditions, it's not systematic in a way that it would be useful to model it.

It makes more sense to determine the residual error in an empirical design, e.g. by TDR measurements, and compensate it.
 

I think parametrized or scalable models are possible.
 

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I fear, I don't grasp the physical meaning of the three T-connected transmission lines in the "equivalent circuit model".
 

pancho_hideboo said:
I think parametrized or scalable models are possible.
Click to expand...

The second model is generic (could even represent a short line segment) and as VvM wrote, this is likely not for the connector but for the assembly with mounting issues (gap in ground path-> series inductance, trace width at connection -> shunt cap).

The first model looks wrong for proper SMA connectors that are properly mounted.
If this post refers to your 90° SMA with layout from https://www.edaboard.com/showthread.php?t=367538&p=1574182&viewfull=1#post1574182

90° SMA are not so great. Your trouble is from mostly layout (via pad capacitance, series inductance from 90° bend). Also, the center pin for through-hole SMA can acts like an open ended line if it is too long (your first schematic).

Model of proper 0° SMA conncetor + proper layout: short segment of 50 Ohm line.
 

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