Lab Project - EE 421L 

Authored by Adrian Lopez-Macuaran,

lopezmac@unlv.nevada.edu

November 21, 2021

  

                             
 Project Description

For this project we are designing a register file (RF)  that contains 32 words and each word contains 8-bits. 

-The RF utilized a 5-bit address using a 5-input NAND gate in order to determine which of the 32 words are being accessed. 

-8 input and output lines will be utilized for reading and writing. 

                             

Project Procedure

             
SRAM Cell
the firsrt part of the project design is making the Static Random Access Memory (SRAM). This cell contains 1-bit of data. The SRAM is made of two inverters sized 1.5u/1.5u, and two NMOS transistors. The NMOS transistors are used because NMOS cant pass logic '1' well.
SRAM Schematic

                 
The following will show the layout,extract,DRC,LVS, and symbol of the SRAM Cell

                     

                   
SRAM Symbol

                 
Following I will show The Simulation schematic and results.        

From the results we can see the SRAM is working as expected storing data when the word line is a logic '1'.

                       
8-Bit Word Schematic and symbol
Our word is made from 8 SRAM cells.
 
               
Following I will show the Layout, Extract, DRC, LVS

                       

                           

                                           
Following I will show The Simulation schematic and results.

                             
    
From the results we can see the SRAM is working as expected storing data when the word line is a logic '1'. In this case as well we are looking at the work located at B<0>.
                                 
32-bit Word Array and Symbol
32-Bit word is made from the 8-bit word previously made. This array lets us know what word is being accessed.
 
                 
Following I will show the Layout, Extract, DRC, LVS

       


                       
Following I will show The Simulation schematic and results.

                             
From the results we can see the SRAM is working as expected storing data when the word line is a logic '1'. In this case as well we are looking at the work located at B<0>.

5-input NAND Gate and Symbol
The NAND Gate will be used to help implent the Row Codecoder having 5-inputs and one output.

                   
Following I will show the Layout, Extract, DRC, LVS


             
Following I will show The Simulation schematic and results.


The results show that the nand gate is working as expected
                                                 
Row Decoder with a zoomed in portion
The row decoder lets us know what 8-bit cell is being accessed.
 

Following I will show the Symbol, Layout, Extract, DRC, LVS


                             
Register File (RF) and Symbol.
The RF is made up of 32-word array, 8-bit Word, SRAM, and Row Decoder.

                     
Following I will show the Layout, Extract, DRC, LVS


               
RF Simulations


                   
From the Word Line(R) pulsing from 0-5 causes the RF to write when its a logic '0'. Bi<0> will be written into the adress 11111 cell. When the Word line changed to a logic '1' the RF will be in read mode and the value in 11111 will be the ouput for B<0>.
                       
Conclusion
From the results of my simulaiton are correct, the issue I had was my ouput was not ouputting the whole 5v. While reading more about RF the solution to this to incorporate a charge line to cause to achieve full logic levels.
                   
RF Project Zip File
Rf_zip                  
                   
                 

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