Finding the width of a pin

[LaserJon]

Hello,

I haven’t been able to figure out how to find the width of a pin.  Is there a way to read the information, something like typing cellname.pin[‘a0’].width?  This would help me design some custom connector functions by just passing cells or pins and not explicitly adding a pin width.  Having to specify the pin width in two places increases chances of error.

Thanks,

Jon

[Xaveer]

Hi Jon,

You guessed correctly:

import nazca as nd
import nazca.demofab as demo

taper = demo.deep.taper(length=5, width1=2, width2=4).put()
print(taper.pin["a0"].width, taper.pin["b0"].width)

nd.export_gds()

Make sure to add those properties when setting the nd.Pin of your cell.

Xaveer

[LaserJon]

Thanks Xaveer.  I’m not sure how I missed this.  I probably tried it on a pin where the width was not defined, and got ‘None’ back.  Anyway I will use this from now on.

Jon

[LaserJon]

Hello, I have a follow-on question here.

I’m trying to do some interconnects where I make all curvature changes continuous, and log the total path length in the cell. Below is an example of how I did it.

Do you see any issue with adding to the dictionary cell[‘properties’]?  For instance I was afraid it might mess up use of the @hashme decorator.

Thanks, Jon

with nd.Cell(hashme=True, autobbox=True) as cell:
    curve = nd.Polygon(points=poly_pts, layer=layer).put(0)
    nd.Pin('a0', width=width).put(0, 0, 180)
    nd.Pin('b0', width=width).put(x1, y1, ang1)
    nd.put_stub()
    cell.properties['parameters']['curvature'] = {'a0':curve_in, 'b0':curve_out}
    cell.properties['parameters']['length'] = pathlength

[Ronald]

Dear Jon,

The properties dict works fine as you use it.

Note that from Nazca >0.5.12 there will be a pin.radius attribute to store the radius directly in the pin. This also allows pin2pin DRC on connections, in addition to xs, width, angle and symmmetry checks.

Ronald

[LaserJon]

Dear Ronald,

Thank you! This also won’t be much effort to update once the new version comes out with the radius attribute.

Jon

[LaserJon]

Adding for anyone using the forum as a reference, this line from the example above can be replaced:

cell.properties[‘parameters’][‘length’] = pathlength

Instead use:

cell.length_geo = pathlength

This enables the path length to be used in the nazca.trace module to find total path lengths of several elements’ paths.

[Author]

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