[G0HZU_JMR]

If it helps I dug out a reel tape of MMBF4416A (purchased at Farnell) and stuck one in a microwave test fixture that gets used with a lab VNA to measure 2 port s-parameters of SMD parts (using bias tees).

I have two types of reversible fixture here and because the results were so close I measured it with both fixtures. The VNA power has to be set very low to prevent non-linear effects in the device. This has to be a genuine small signal measurement.

The idea is to configure the device in common gate and then swap the precision fixture around and take s2p data to 2GHz when biased at 5.000Vds and 1.000mA Id. This effectively swaps the role of drain and source.

The first surprise was that the dc operating point was exactly the same when the device was swapped around when in common (grounded) gate mode. The bias current didn't change even by 1uA. The operating point stayed within 1mV or so after the drain and source swap.

See below for a plot of the s2p data after it was used to design a common gate RF amp at 125MHz. This is a highly critical test to see how symmetric the part was. I have to confess there is a slight fudge factor cheat in the 'corrected' plot as to get perfect overlay I had to add about 0.15pF at the drain on the 'regular' pinout version. This happened exactly the same with the other fixture so I suspect that the device is quite symmetric but there is probably some stray capacitance in the die somewhere that just spoils the symmetry ever so slightly. See the second (uncorrected plot to see what I mean) It only takes just over 0.1pF to shift the amplifier response sideways like this.

I do think this difference is inside the device but it is a tiny difference in my opinion. I have a lot of experience of taking device models like this so I think the results are realistic.