EDB: fully parametrized CPWG design

This example shows how you can use HFSS 3D Layout to create a parametric design for a CPWG (coplanar waveguide with ground).

Perform required imports

Perform required imports. Importing the Hfss3dlayout object initializes it on version 2023 R2.

import os

import numpy as np

from pyedb.dotnet.edb import Edb
from pyedb.generic.general_methods import (
    generate_unique_folder_name,
    generate_unique_name,
)

Set non-graphical mode

Set non-graphical mode. The default is False.

non_graphical = False

Launch EDB

Launch EDB.

aedb_path = os.path.join(generate_unique_folder_name(), generate_unique_name("pcb") + ".aedb")
print(aedb_path)
edbapp = Edb(edbpath=aedb_path, edbversion="2024.1")

C:\Users\ansys\AppData\Local\Temp\pyedb_prj_J69\pcb_VWGSUR.aedb

Define parameters

Define parameters.

params = {
    "$ms_width": "0.4mm",
    "$ms_clearance": "0.3mm",
    "$ms_length": "20mm",
}
for par_name in params:
    edbapp.add_project_variable(par_name, params[par_name])

Create stackup

Create a symmetric stackup.

edbapp.stackup.create_symmetric_stackup(2)
edbapp.stackup.plot()

Material 'copper' does not exist in material library. Intempt to create it from syslib.
Material 'FR4_epoxy' does not exist in material library. Intempt to create it from syslib.
Material 'SolderMask' does not exist in material library. Intempt to create it from syslib.

<module 'matplotlib.pyplot' from 'C:\\actions-runner\\_work\\pyedb\\pyedb\\.venv\\lib\\site-packages\\matplotlib\\pyplot.py'>

Draw planes

Draw planes.

plane_lw_pt = ["0mm", "-3mm"]
plane_up_pt = ["$ms_length", "3mm"]

top_layer_obj = edbapp.modeler.create_rectangle(
    "TOP", net_name="gnd", lower_left_point=plane_lw_pt, upper_right_point=plane_up_pt
)
bot_layer_obj = edbapp.modeler.create_rectangle(
    "BOTTOM", net_name="gnd", lower_left_point=plane_lw_pt, upper_right_point=plane_up_pt
)
layer_dict = {"TOP": top_layer_obj, "BOTTOM": bot_layer_obj}

Draw trace

Draw a trace.

trace_path = [["0", "0"], ["$ms_length", "0"]]
edbapp.modeler.create_trace(
    trace_path, layer_name="TOP", width="$ms_width", net_name="sig", start_cap_style="Flat", end_cap_style="Flat"
)

<pyedb.dotnet.edb_core.edb_data.primitives_data.EdbPath object at 0x000001AA482A2F20>

Create trace to plane clearance

Create a trace to the plane clearance.

poly_void = edbapp.modeler.create_trace(
    trace_path,
    layer_name="TOP",
    net_name="gnd",
    width="{}+2*{}".format("$ms_width", "$ms_clearance"),
    start_cap_style="Flat",
    end_cap_style="Flat",
)
edbapp.modeler.add_void(layer_dict["TOP"], poly_void)

True

Create ground via padstack and place ground stitching vias

Create a ground via padstack and place ground stitching vias.

edbapp.padstacks.create(
    padstackname="GVIA",
    holediam="0.3mm",
    paddiam="0.5mm",
)

yloc_u = "$ms_width/2+$ms_clearance+0.25mm"
yloc_l = "-$ms_width/2-$ms_clearance-0.25mm"

for i in np.arange(1, 20):
    edbapp.padstacks.place([str(i) + "mm", yloc_u], "GVIA", net_name="GND")
    edbapp.padstacks.place([str(i) + "mm", yloc_l], "GVIA", net_name="GND")

Save and close EDB

Save and close EDB.

edbapp.save_edb()
edbapp.close_edb()

True