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Cadence Setup for ECE 5/415: Analog IC Design

Login to the ENGR server using X2Go Client. Linux and Mac users can use ssh instead of the X2Go client. They can do this with

 ssh -XY [username] 

This page will be modified/edited as we go along the semester to improve the simulation experience. Thus, its a good idea to check it if you run into problems.

Setting up NCSU Library

0) Open the .bashrc file in your home directory

gedit .bashrc

Add the following lines to the .bashrc file in your home directory

source /
export PATH=$PATH:/

Refresh the bash shell

source .bashrc

1) Goto your work directory. Better create a new directory for every course.

mkdir ece515
cd ece515

2) If you have existing files, save backups of the files below

cp .cdsinit  .cdsinit_bkp 
cp cds.lib  cds.lib_bkp 

3) Copy .cdsinit from instructor's directory using the command below to your into ece515 directory

cp    /home/vsaxena/pdk/ncsu-cdk-1.6.0.beta/cdssetup/cdsinit  .cdsinit

4) If you dont have an existing cds.lib file, then copy the cds.lib file using the following command and skip to the next step:

cp    /home/vsaxena/pdk/ncsu-cdk-1.6.0.beta/cdssetup/cds.lib  cds.lib

If you have an existing cds.lib file, then merge the cds.lib file from (/home/vsaxena/pdk/ncsu-cdk-1.6.0.beta/cds.lib) with your existing cds.lib in the directory. This is equivalent to copying the following entries (note that CDK_DIR variable should be defined as in the first line below):

# NCSU Design Kit Path
CDK_DIR = "/home/vsaxena/pdk/ncsu-cdk-1.6.0.beta"

# Include basic Spectre and Verilog-A libraries
DEFINE basic    $CDSDIR/tools/dfII/etc/cdslib/basic
DEFINE analogLib $CDSDIR/tools/dfII/etc/cdslib/artist/analogLib
DEFINE functional    $CDSDIR/tools/dfII/etc/cdslib/artist/functional
DEFINE sbaLib    $CDSDIR/tools/dfII/etc/cdslib/artist/sbaLib
DEFINE ahdlLib $CDSDIR/tools/dfII/samples/artist/ahdlLib
DEFINE bmslib $CDSDIR/tools/dfII/samples/artist/bmslib

# Include NCSU PDK
DEFINE basic $CDK_DIR/lib/basic
DEFINE NCSU_Analog_Parts $CDK_DIR/lib/NCSU_Analog_Parts
DEFINE NCSU_Digital_Parts $CDK_DIR/lib/NCSU_Digital_Parts
--DEFINE MOSIS_Layout_Test $CDK_DIR/lib/MOSIS_Layout_Test
DEFINE NCSU_TechLib_ami06 $CDK_DIR/lib/NCSU_TechLib_ami06
DEFINE NCSU_TechLib_ami16 $CDK_DIR/lib/NCSU_TechLib_ami16
DEFINE NCSU_TechLib_hp06 $CDK_DIR/lib/NCSU_TechLib_hp06
DEFINE NCSU_TechLib_tsmc02 $CDK_DIR/lib/NCSU_TechLib_tsmc02
DEFINE NCSU_TechLib_tsmc02d $CDK_DIR/lib/NCSU_TechLib_tsmc02d
DEFINE NCSU_TechLib_tsmc03 $CDK_DIR/lib/NCSU_TechLib_tsmc03
DEFINE NCSU_TechLib_tsmc03d $CDK_DIR/lib/NCSU_TechLib_tsmc03d
DEFINE NCSU_TechLib_tsmc04_4M2P $CDK_DIR/lib/NCSU_TechLib_tsmc04_4M2P

Please note that we are using 1um and 180nm CMOS models while using NCSU libraries. This may be different from some of the tutorials and setup used in other courses.

5) You should be ready to start Cadence Virtuoso now!

virtuoso &

CMOS Book Examples

You can add CMOS book examples by adding the following line to your cds.lib file

SOFTINCLUDE /home/vsaxena/CMOSedu/cds.lib

Please do not re-download Prof Baker's CMOS Book examples from and/or install the NCSU PDK as directed in the CMOSEdu tutorials. They are already installed and available in your course directory and can be seen in the Cadence Library Manager.

Simulation Models

Simulation models are located in the following directory on the server.


The course uses a combination of long-channel (1um) and short-channel (180nm or 0.18um) CMOS models.

The 1um models (in file cmosedu_models.txt) are for a closer matching to hand-calculations for some of the Homework problems, while 180nm models (in file tsmc018.scs) provides a more realistic design experience in HWs and the project.

Setting up the CMOS Simulation Models

Please follow the instructions below to use the 180nm CMOS models. The method is same for using any other model e.g. 1um model. Its a good idea to open the model file and take a look at the contents.


Note the model location in the slides. Again, we are using NCSU libraries in our setup with 180nm and 1um models. Please don't use alternative setups from other help videos where AMI06 or 0.35um CMOS process were used.

You can see my example schematics by adding the following lines to your cds.lib

/home/vsaxena/ece515/HW1           HW1
/home/vsaxena/ece515/HW1_180n      HW1_180n


I-V and Parametric Sweeps - Thanks to Jubayer!

analog.txt · Last modified: 2017/09/13 00:56 by vsaxena