EDB: parametric via creation

This example shows how you can use EDB to create a layout.

Perform required imports

Perform required imports.

import os

import numpy as np

import pyedb
from pyedb.generic.general_methods import (
    generate_unique_folder_name,
    generate_unique_name,
)

aedb_path = os.path.join(generate_unique_folder_name(), generate_unique_name("via_opt") + ".aedb")

Create stackup

The StackupSimple class creates a stackup based on few inputs. This stackup is used later.

Create ground plane

Create a ground plane on specific layers.

def _create_ground_planes(edb, layers):
    plane = edb.modeler.Shape("rectangle", pointA=["-3mm", "-3mm"], pointB=["3mm", "3mm"])
    for i in layers:
        edb.modeler.create_polygon(plane, i, net_name="GND")

Create EDB

Create EDB. If the path doesn’t exist, PyAEDT automatically generates a new AEDB folder.

edb = pyedb.Edb(edbpath=aedb_path, edbversion="2024.1")

Create stackup layers

Create stackup layers.

layout_count = 12
diel_material_name = "FR4_epoxy"
diel_thickness = "0.15mm"
cond_thickness_outer = "0.05mm"
cond_thickness_inner = "0.017mm"
soldermask_thickness = "0.05mm"
trace_in_layer = "TOP"
trace_out_layer = "L10"
gvia_num = 10
gvia_angle = 30
edb.stackup.create_symmetric_stackup(
    layer_count=layout_count,
    inner_layer_thickness=cond_thickness_inner,
    outer_layer_thickness=cond_thickness_outer,
    soldermask_thickness=soldermask_thickness,
    dielectric_thickness=diel_thickness,
    dielectric_material=diel_material_name,
)

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.

True

Create variables

Create all variables. If a variable has a $ prefix, it is a project variable. Otherwise, is a design variable.

giva_angle_rad = gvia_angle / 180 * np.pi

edb["$via_hole_size"] = "0.3mm"
edb["$antipaddiam"] = "0.7mm"
edb["$paddiam"] = "0.5mm"
edb.add_design_variable("via_pitch", "1mm", is_parameter=True)
edb.add_design_variable("trace_in_width", "0.2mm", is_parameter=True)
edb.add_design_variable("trace_out_width", "0.1mm", is_parameter=True)

(True, <Ansys.Ansoft.Edb.Utility.VariableServer object at 0x000001AA6E681E80>)

Create definitions

Create two definitions, one for the ground and one for the signal. The definitions are parametric.

edb.padstacks.create(
    padstackname="SVIA",
    holediam="$via_hole_size",
    antipaddiam="$antipaddiam",
    paddiam="$paddiam",
    start_layer=trace_in_layer,
    stop_layer=trace_out_layer,
)
edb.padstacks.create(padstackname="GVIA", holediam="0.3mm", antipaddiam="0.7mm", paddiam="0.5mm")

'GVIA'

Place padstack for signal

Place the padstack for the signal.

edb.padstacks.place([0, 0], "SVIA", net_name="RF")

<pyedb.dotnet.edb_core.edb_data.padstacks_data.EDBPadstackInstance object at 0x000001AA56246710>

Place padstack for ground

Place the padstack for the ground. A loop iterates and places multiple ground vias on different positions.

gvia_num_side = gvia_num / 2

if gvia_num_side % 2:
    # Even number of ground vias on each side
    edb.padstacks.place(["via_pitch", 0], "GVIA", net_name="GND")
    edb.padstacks.place(["via_pitch*-1", 0], "GVIA", net_name="GND")
    for i in np.arange(1, gvia_num_side / 2):
        xloc = "{}*{}".format(np.cos(giva_angle_rad * i), "via_pitch")
        yloc = "{}*{}".format(np.sin(giva_angle_rad * i), "via_pitch")
        edb.padstacks.place([xloc, yloc], "GVIA", net_name="GND")
        edb.padstacks.place([xloc, yloc + "*-1"], "GVIA", net_name="GND")

        edb.padstacks.place([xloc + "*-1", yloc], "GVIA", net_name="GND")
        edb.padstacks.place([xloc + "*-1", yloc + "*-1"], "GVIA", net_name="GND")
else:
    # Odd number of ground vias on each side
    for i in np.arange(0, gvia_num_side / 2):
        xloc = "{}*{}".format(np.cos(giva_angle_rad * (i + 0.5)), "via_pitch")
        yloc = "{}*{}".format(np.sin(giva_angle_rad * (i + 0.5)), "via_pitch")
        edb.padstacks.place([xloc, yloc], "GVIA", net_name="GND")
        edb.padstacks.place([xloc, yloc + "*-1"], "GVIA", net_name="GND")

        edb.padstacks.place([xloc + "*-1", yloc], "GVIA", net_name="GND")
        edb.padstacks.place([xloc + "*-1", yloc + "*-1"], "GVIA", net_name="GND")

Generate traces

Generate and place parametric traces.

edb.modeler.create_trace(
    [[0, 0], [0, "-3mm"]],
    layer_name=trace_in_layer,
    net_name="RF",
    width="trace_in_width",
    start_cap_style="Flat",
    end_cap_style="Flat",
)

edb.modeler.create_trace(
    [[0, 0], [0, "3mm"]],
    layer_name=trace_out_layer,
    net_name="RF",
    width="trace_out_width",
    start_cap_style="Flat",
    end_cap_style="Flat",
)

<pyedb.dotnet.edb_core.edb_data.primitives_data.EdbPath object at 0x000001AA561BFB20>

Generate ground layers

Generate and place ground layers.

ground_layers = [i for i in edb.stackup.signal_layers.keys()]
ground_layers.remove(trace_in_layer)
ground_layers.remove(trace_out_layer)
_create_ground_planes(edb=edb, layers=ground_layers)

Plot Layout

Generate and plot the layout.

# edb.nets.plot(layers=["TOP", "L10"])
edb.stackup.plot(plot_definitions=["GVIA", "SVIA"])

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

Save EDB and close

Save EDB and close.

edb.save_edb()
edb.close_edb()

print("aedb Saved in {}".format(aedb_path))

aedb Saved in C:\Users\ansys\AppData\Local\Temp\pyedb_prj_OX7\via_opt_SZ4UVP.aedb