Calculate Delay of inverter in LTspice

[nobrainer612]

Homework Statement

I am trying to calculate the delay of the inverter.

Homework Equations

The Attempt at a Solution

I tried to build the circuit in LTspice, but seems like I couldn't get anything useful from the plot. So I am hope somebody good in LTspice take a look with this and hope they know what I did wrong. I am just trying to find the delay of the inverter built by PMOS and NMOS.
Thank you

 

[KataKoniK]

for your post and for sharing your attempt at solving the problem. In order to accurately calculate the delay of the inverter, there are a few key factors that need to be taken into consideration. These include the transistor characteristics, the load capacitance, and the parasitic capacitances present in the circuit.

Firstly, it is important to ensure that the transistor models used in LTspice accurately represent the physical transistors being used in the circuit. This includes parameters such as threshold voltage, channel length, and width. If these parameters are not accurately represented, the simulation results may not be reliable.

Next, the load capacitance should be properly accounted for in the simulation. This includes both the internal capacitance of the transistors as well as any external capacitance connected to the output node. The load capacitance will affect the rise and fall times of the output signal, which in turn affects the overall delay of the inverter.

Lastly, parasitic capacitances in the circuit can also have a significant impact on the delay of the inverter. These include the capacitances between the different layers of the transistors, as well as the capacitances between different nodes in the circuit. These parasitic capacitances can be minimized through careful layout and design techniques, but they should still be considered in the simulation.

In order to accurately calculate the delay of the inverter, it may be helpful to use a more detailed simulation tool such as HSPICE or Cadence Spectre. These tools allow for more precise modeling of the transistor and circuit parasitics, which can give a more accurate result.

I hope this helps and good luck with your simulation!