path-analysis 0.4.1

Description:

pathanalysis 0.4.1

Path Length Analysis



Table of contents

Path Length Analysis
Table of contents

Introduction
Current-Status
Folder Structure
Prerequisites
Installation
Usage

Example


About Mabrains
Contact-Us
License



Introduction
Measuring and optimizing path lengths in resistive paths for integrated circuits and photonic paths are fundamental aspects of design and layout optimization. It directly influences signal integrity, performance, propagation delay, power efficiency, phase matching, and the overall functionality of electronic and photonic systems.
Current-Status

:warning: We are currently treating the current content as an experimental preview!

The tool will be tagged with a production version when ready to do.
Folder Structure
📁 path_length_analysis
┣ 📁path_analysis Includes path_length tool script.
┣ 📁images Contains images used for illustration.
┣ 📁.github Includes CI workflows for github actions.
┣ 📜Makefile To make some tests for path_length_analysis tool.
┣ 📜requirements.txt List of python packages required for tool installation.
┣ 📜requirements.test.txt List of python packages required for testing purpose.
┣ 📜path_length.py Python script to calculate path length for a gds file.
┣ 📜setup.py Python script used for package setup.
┣ 📜.flake8 Includes flake8 configuration setup.
┣ 📜.gitignore Excludes certain local files from being pushed to Git.
┗ 📜README.md This file that describes the contents.


Prerequisites
At a minimum:

python 3.9+
python3-venv

To install a virtual environment for ubuntu 22.04:
python3 -m pip install --user virtualenv
# OR
sudo apt-get install -y python3-venv

Installation
To install the path length tool from source, you could run the following commands:
git clone https://github.com/mabrains/path_length_analysis.git
cd path_length_analysis/

python3 -m venv ./env
source ./env/bin/activate

python3 setup.py install

Usage
This tool calculates the path length based on the presence of the cutting shape on the path you need to measure it accompanied by a text that refers to the cutting name, you could consider it as a port on the path you have.
As shown in the following figure, we could measure the path length between the start & end ports.




Fig. 1. Path length sample for illustration


NOTE: The text should be inside the cutting shape, the cutting shape and its text are on the same layer,

Before running the python script that measure the path length for layout routes, you have to complete some configurations in config.yaml file, and they all are declared in the table below:



Parameter
Description
Selection




gds_file
Path of layout file you need to measure its paths
Required


cell_name
Name of top cell in your layout if you have more one cell
Optional


path_layer
Tuple of two integers for path layer number and data type
Required


cutting_layer
Tuple of two integers for cutting layer number and data type
Required


nodes
Ports of interest to be filtered, corresponds to text placed on cutting polygons
Optional




The path_length.py script takes your config file to run path length analysis on it and save run logs and results.
You could find the run results at your run directory if you previously specified it through --run_dir=<run_dir_path>, default path of run directory is length_run_<date>_<time> in current directory.
python3 path_length.py (--help| -h)
python3 path_length.py (--config=<config_file_path>) [--run_dir=<run_dir_path>]

Options

--help -h Print this help message.
--config=<config_file_path> Yaml file contains the path length parameters.
--run_dir=<run_dir_path> Run directory to save all the results [default: pwd].


Example
python3 path_length.py --config=tests/lidar_no_rad.yaml --run_dir=lidar_no_rad_results

Input-Config
gds_file: tests/lidar_no_rad.gds
cell_name: lidar
path_layer:
layer_no: 1
layer_dtype: 0
cutting_layer:
layer_no: 1
layer_dtype: 10
nodes:
- splitter_p1_start
- splitter_p1_end
- splitter_p2_start
- splitter_p2_end

Input-Test




Fig. 2. Path length example for lidar layout

Output-Result



port1
port2
length (um)




splitter_p1_start
splitter_p1_end
526.1392525630397


splitter_p3_start
splitter_p3_end
501.1340271504263



We could notice that both paths are identical except for the vertical distance shown in the previous figure.
** diff_vertical_part = 35.5 - 10.5 = 25um
** diff_total_length = 526.1 - 501.1 = 25um

About Mabrains
Mabrains was founded to achieve the main purpose to change the world of Chip Design using AI. Empowering the world with a new methodologies and techniques that would disrupt the status quo in the EDA industry.
We have contributed in developing many PDKs for Open Source Tools. For more information, please refer to Mabrains-Github.
Contact-Us
Requests for more information about Path Length tool and other open source technologies can be submitted via this web form.
License
The Path Length tool is released under the GNU Lesser General Public License - Version 3
The copyright details (which should also be found at the top of every file) are;
# SPDX-FileCopyrightText: 2024 Mabrains Company
# Licensed under the GNU Lesser General Public License, Version 3.0 (the "License");
# you may not use this file except in compliance with the License.

# GNU Lesser General Public License
# Version 3, 29 June 2007

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
# SPDX-License-Identifier: LGPL-3.0