Hi Guys,(adsbygoogle = window.adsbygoogle || []).push({});

I am stuck at a point and needs help.

The thing is I am doing MOSFET inverters using Pspice.

I am getting its VTC (voltage characteristic Curve) But I don't know how to get derivative of this curve in order to obtain some parameters required for Noise margin.

Here is the file:

.model NMOD NMOS (LEVEL=1, VTO=0.6 GAMMA=0 LAMBDA=0 KP=60U)

.model PMOD PMOS (LEVEL=1, VTO=-0.8 GAMMA=0 LAMBDA=0 KP=20U)

***********

* CIRCUIT *

***********

VDD 3 0 DC 3

VGS 1 0 DC 3

M1 2 1 0 0 NMOD L=0.8U W=2U

M2 2 1 3 3 PMOD L=0.8U W=10U

.OP

.DC LIN VGS 0 3 0.1

.PLOT DC V(2)

.PROBE

.END

I have 9.1 Student ,Demo version. I referred to user manual.... and it says I used use probe function 'd()' to get derivative but thats not working. It says invalid expressions.

I am taking 'd()' at 'V(2)'.

I would really appreciate if some one can help me out.

Thanks,

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Pspice: derivative function in probe

**Physics Forums | Science Articles, Homework Help, Discussion**