Thanks a lot!PDSOI should not let the body float. The body is substantial and
contains a parasitic NPN or PNP. With its base open, if you don't tie
the body. Any D-B leakage will see BJT current gain. Then you get
things like a stark drain kink effect, history effects (gate pumps
body, now you've got "deltaVT by DRAM").
PDSOI with its body tied correctly, looks just like JI. Except for the
NWell not being a humongous leaky diode to PSub. And The NMOS
body not being pinned to Psub. Both of which are handy.
Anything analog, I'd pick PDSOI (properly tied) over FDSOI, other
than a bang-bang switch (linearity there, is superior owing to the
FDSOI having no S, D bottom plate junction, only oxide C.