Changing Vth (Threshold voltage) in Cadence

dick_freebird said:

The easiest approach is simply to put a series voltage source
between the FET gate and its driving source, with (say) v=dVTN
to make the (effective) VT variable from within ADE.

Otherwise you need to drill down into the models/spectre dir
and edit the pertinent FET model card, making its VT0 (or
whatever your particular model uses) a Spectre variable if
it's presently a fixed item, or add an "adder" (like if it's
VT0=avtn+dvtn(), make it VT0=avtn+dvtn()+myvtn and
add myvtn to your variables list.

If the PDK is outside your authority to edit, then make a
local copy and have at it, and link it instead of the default.

Most modern processes probably offer you either corners
or MC access to device params, and you may already
have those "hooks" if you inquire of the foundry modeling
people or your own CAD group.

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