Nov 23, 2005 · The slope of this line is the subthreshold slope. It represents how fast the Ids ramps up for an increase of Vgs. Steep slope means the device gets out of the subthreshold region faster or in other words has lower Vth and therefore conduct better. It is usually given as kT/q*log(1+Cd/Ci).

Oct 16, 2014 · Subthreshold swing is also the inverse of the subthreshold slope. On a graph of Ids(Vgs) with logarithmic (base 10) axis for Ids the subthreshold slope is found as the straight-line approximation of the subthreshold current, normally expressed in units of decades/mV. Subthreshold swing is expressed in units of mV/decade.

May 26, 2021 · I have a number of Vg vs Id data sets/plots for a transistor under a number of different conditions that I need to extract the subthreshold slope from but I am not sure the best way to do it. I have done some rough hand calculations subtracting a gate voltage from another over a decade of drain current change in the subthreshold region but I am ...

Sep 10, 2017 · \$\begingroup\$ "large subthreshold slope and hence, at sub threshold values of Vgs, there'll be a larger value of current than otherwise" <- Why? If a line has positive slope, and you go further left on the graph, the y-value goes down. If the slope increases, you go down even more. The y-value in this case would be current. \$\endgroup\$ –

Apr 25, 2018 · However, the subthreshold regime is pretty nice: The reason that you could consider subthreshold "slow" is that the current is lower and it takes longer to charge a gate capacitor of a fixed size; however, you have fewer higher order effects. For the best power processing per-Watt, you can just design to run in subthreshold at near threshold.

Aug 11, 2020 · The MOSFET physics posits and proves that this subthreshold swing (reciprocal SS, [subthreshold swing] = 1/[subthreshold slope]) cannot be less than ca. 60 mV/decade. For BTBT TFET, a subthreshold region can be coarsely defined as the region where the conduction band of the intrinsic region is still not aligned with the valence band of the P ...

Nov 8, 2017 · Sub-threshold slope factor is given by : Cd = depletion capacitance Cox= oxide capacitance How to calculate the Sub-threshold slope factor for different technology nodes? I m able to substitute for Cox but i don't know how to calculate Cd...i m using the basic inverter circuit

Jul 7, 2019 · When Vds is roughly >100mV, Vgs is about or smaller than Vth, and there is some current flow from D to S. This is called the "subthreshold condition" You will only see this when you are plotting Id vs Vgs since the current is exponentially dependent on Vgs. This also means you will not be able to tell when you are looking at Id vs Vds curve.

Jul 25, 2016 · Subthreshold operation is normally used at very low currents for Class A micropower (or nanopower) circuits. Linear power amplifiers operate in the saturation region at much higher currents. The transistors in a complementary Class AB or B amplifier may rapidly go through the subthreshold region when amplifying an AC signal but that is not ...

Mar 21, 2024 · LTspice does allow post-processing of a TRANsient run for a slope measurement. You can use the .OP button to add the slope measurement. In this case, the result slope_V(out) shows up in the SPICE ERROR LOG window:.meas TRAN slope_V(out) MAX d(V(out))/d((time)) Note that a small time step is required for an accurate result.