EE 421L

Lab 5  


Authored by Jeremy Morgan

Email: morgaj7@unlv.nevada.edu

Due: 10/11/2017


Pre-lab:

Back-up all of your work from the lab and the course.
Go Through Tutorial 3

Lab:
   
Part 1: 
Draft schematics, layouts, and symbols for two inverters)

12u/6u Inverter:
(width of the PMOS / width of the NMOS with both devices having minimum lengths of 0.6u)

   
    Schematic:                                                                                         Symbol View:
lab%205%20images/1_inverter_schematic.JPG    lab%205%20images/1_inverter_SYMBOL.JPG

For the Layout and Extracted view, only used 1 row of contacts on VDD and Ground to reduce layout size.
Layout requires 4 pins : Ai - A - Gnd - VDD
The schematic only needs two pins: A - Ai

    Layout View:                              Extracted View:
lab%205%20images/1_inverter_layout.JPG         lab%205%20images/1_inverter_extracted.JPG     

DRC the 12u/6u inverter layout:
lab%205%20images/1_inverter_drc.JPG

LVS of the 12u/6u Inverter Schematic with the Extracted Layout to see if they match:
lab%205%20images/1_inverter_LVS.JPG
The Netlists Match

48u/24u Inverter:
(Device uses 4x multiplyer [ m = 4] to achieve 48u/24u inverter)

(m=4 is detailed within the schematic below)
   
    Schematic:                                                                                         Symbol View:
    
lab%205%20images/2_inverter_schematic.JPG    lab%205%20images/2_inverter_SYMBOL.JPG

For the Layout and Extracted view, only used 1 row of contacts on VDD and Ground to reduce layout size.
Layout requires 4 pins : Ai - A - Gnd - VDD
The schematic only needs two pins: A - Ai


    Layout View:                                      Extracted View:
lab%205%20images/2_inverter_layout.JPG           lab%205%20images/2_inverter_EXTRACTED.JPG   

DRC the 48u/24u inverter layout:
lab%205%20images/1_inverter_drc.JPG

LVS of the 48u/24u Inverter Schematic with the Extracted Layout to see if they match:
lab%205%20images/2_inverter_LVS.JPG 
The Netlists Match

Part 2
Using SPICE and ULTRASIM simulate the operation of both inverters driving a 100 fF, 1 pF, 10 pF, and 100 pF capacitive load)

12u/6u Inverter:

100fF Capactive Load:


    Schematic:                                                                                            SPICE:
lab%205%20images/3_100f_SCHEMATIC.JPG     lab%205%20images/3_100f_ADL.JPG   
    UltraSim:                                                                                     
lab%205%20images/3_100f_ADL.JPG  

1pF Capactive Load:

    Schematic:                                                                                            SPICE:
lab%205%20images/3_1p_SCHEMATIC.JPG     lab%205%20images/3_1p_ADL.JPG   
    UltraSim:                                                                                     
lab%205%20images/3_1p_ADL.JPG 

10pF Capactive Load:

    Schematic:                                                                                            SPICE:
lab%205%20images/3_10p_SCHEMATIC.JPG     lab%205%20images/3_10p_ADL.JPG
    UltraSim:                                                                                     
lab%205%20images/3_10p_ADL.JPG 

100pF Capactive Load:

    Schematic:                                                                                            SPICE:
lab%205%20images/3_100p_SCHEMATIC.JPG      lab%205%20images/3_100p_ADL.JPG
UltraSim:            
lab%205%20images/3_100p_ADL.JPG                                                                        

From the above schematics and spice responses one can deduce that the capicitative load has had an effect on the waveform of Ai.
The time delay between A and for Ai to map is increased with the capacitative load.
Due to this fact the waveforms of Ai also become sharper/steeper as the capacitance increased because of the output signal being dimished in quality.
This diminshment in quality is due to the fact that the capacitors could not reach a fully charged state in the time between pulses.


48u/24u Inverter:

100fF Capactive Load:


    Schematic:                                                                                            SPICE:
lab%205%20images/4_100f_SCHEMATIC.JPG     lab%205%20images/4_100f_ADL.JPG   
    UltraSim:                                                                                     
lab%205%20images/4_100f_ADL.JPG  

1pF Capactive Load:

    Schematic:                                                                                            SPICE:
lab%205%20images/4_1p_SCHEMATIC.JPG     lab%205%20images/4_1p_ADL.JPG   
    UltraSim:                                                                                     
lab%205%20images/4_1p_ADL.JPG 

10pF Capactive Load:

    Schematic:                                                                                            SPICE:
lab%205%20images/4_10p_SCHEMATIC.JPG     lab%205%20images/4_10p_ADL.JPG
    UltraSim:                                                                                     
lab%205%20images/4_10p_ADL.JPG 

100pF Capactive Load:

    Schematic:                                                                                            SPICE:
lab%205%20images/4_100p_SCHEMATIC.JPG      lab%205%20images/4_100p_ADL.JPG
    UltraSim:                                                                                     
lab%205%20images/4_100p_ADL.JPG
The above schematic and graphing for the 48u/24u inverter show the same trend as the 12u/6u inverter's results.
Once again it can be seen that the time delay between A and for Ai to map is increased with the capacitative load.
And as previously stated, due to this fact, the waveforms of Ai also become sharper/steeper as the capacitance increased because of the output signal being dimished in quality.
However with the 48u/24u inverter being used, the diminishing of quality and time delay were less exagerated then the 12u/6u counterpart up to a certain point.

Lab 5 Files: HERE
    

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