Lab 5 - EE 421L
Authored by Surafel Abera
Abera@unlv.nevada.edu
October 11, 2017
Pre-lab work:
Lab
work Back-up | Tutorial 3 completed |
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Lab work:
Inverter Schematics
12u/6u inverter | 48u/24u inverter |
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The schematic on the left is an inverter of (12u/6u) composed of four terminal NMOS W=6u L=0.6u , PMOS W=12u, L=0.6u.
The
schematic on the right is four inverters in parallel [4* (12u/6u) =
(48u/6u)]. Each inverter NMOS W=6u L=0.6u , PMOS W=12u, L=0.6u.
The 48u/24u inverter performs 4 times better than the 12u/6u inverter.
12u/6u Symbol | 48u/24u Symbol |
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12u/6u Layout | 48u/24u Layout |
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In the layout the inverter terminals are handled differently than the schematics.
The body of the Pmos is connected to global vdd! through ntap.
The body of the Nmos is connected to ground (gnd!).
The layout of 48u/12u has 4 gates, sources, and drains that are connected together.
12u/6u DRC and LVS | 48u/24u DRC and LVS |
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Specter and UltraSim Simulation of 12u/6u inverter
12u/6u inverter driving 100fF capacitor | Simulated using Specter | Simulated using UltraSim |
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12u/6u inverter driving 1pF capacitor | Simulated using Specter | Simulated using UltraSim |
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12u/6u inverter driving 10pF capacitor | Simulated using Specter | Simulated using UltraSim |
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12u/6u inverter driving 100pF capacitor | Simulated using Specter | Simulated using UltraSim |
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The
12u/6u inverter drives the smaller capacitor loads one time, but as the
load capacitance is increased it took longer time to charge the
larger capacitor. The plots of the Specter and UltraSim plots are equal. |
Specter and UltraSim Simulation of 48u/24u inverter
48u/24u inverter driving 100fF capacitor | Simulated using Specter | Simulated using UltraSim |
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48u/24u inverter driving 1pF capacitor | Simulated using Specter | Simulated using UltraSim |
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48u/24u inverter driving 10pF capacitor | Simulated using Specter | Simulated using UltraSim |
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48u/24u inverter driving 100pF capacitor | Simulated using Specter | Simulated using UltraSim |
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The
48u/24u inverter performs better than the 12u/6u inverter in driving
the different size of capacitors because it has he larger channel to
conduct current. The plots of the Specter and UltraSim plots are equal. |
Lab5 files
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