CE338 Lab 2020 Spring
Lab 5
Name: Braden Morrow
Email: bdmorrow@fortlewis.edu
1. Lab 5 - Inverter
2. Introduction
The purpose of
this lab was to be able to design and simulate an inverter in
ElectricVLSI. An inverter with 5x capacity was also built and simulated
to this end.
3. Results
The first task was to create a schemtic for an inverter using the
NMOS and PMOS MOSFETs we created in the last lab. This code shows a
simulation being ran with a pulse input.
Figure 1. 20/10 Inverter Schematic and Simlation Code
These simulations show the results from the above schematic with both a constantly increasing input and a pulse input.
Figure 2. Results from Constantly Increasing Input on 20/10 Inverter
Figure 3. Results from Pulse Input on 20/10 Inverter
The second task was to create a layout for this inverter. The layout which was DRC and NCC error free can be seen below.
Figure 4. 20/10 Inverter Layout and Error Checks
The third task was to create
a new inverter using the multiplier function provided by LTSpice. The
below pictures show the schematic and layout of that device which are
DRC and NCC error free.
Figure 5. 100/50 Inverter Schematic
Figure 6. 100/50 Inverter Layout
The fourth task was to
simulate both the 20/10 Inverter and 100/50 Inverter with 100fF, 1pF,
and 10pF loads. The first three simulations are using the 20/10
Inverter, while the last three are using the 100/50 Inverter. Clearly,
the 100/50 Inverter can drive larger loads than the 20/10 Inverter.
Figure 7. 20/10 Inverter Driving 100fF Load
Figure 8. 20/10 Inverter Driving 1pF Load
Figure 9. 20/10 Inverter Driving 10pF Load
Figure 10. 100/50 Inverter Driving 100fF Load
Figure 11. 100/50 Inverter Driving 1pF Load
Figure 12. 100/50 Inverter Driving 10pF Load
The fifth task was to build
out the below schematic, and then use it to explore other simulation
tools available in ElectricVLSI. The first simulation is using the
built-in ALS Simualtion tool, while the second was using the built-in
IRSIM tool.
Figure 13. Dual Inverter Schematic
Figure 14. Dual Inverter ALS Simulation
Figure 15. Dual Inverter IRSIM Simulation
5. Discussion
This lab
let use our formerly created LTSpice MOSFETS in order to build a working inverter. While working in ElectricVLSI
during this lab, I really appreciated the layout cells and how they
display the actual physical properties of the schematics. This became a
lot more apparent than in previous examples when we built the 100/50
Inverter as we had to physically scale up its layout. I also
appreciated learning about other simulation tools in ElectricVLSI as I
can see the real-time simulation being helpful in the future for
trouble shooting or verifying logic as the system in being built.
