PlaceAndConnect¶
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class
picazzo3.routing.place_route.cell.
PlaceAndConnect
(*args, **kwargs)¶ Parametric Cell for manual placement and Logical connection of components.
The user supplies a dictionary of the instances of child cells that need to be placed through the property
child_cells
. This dictionary maps the instance names to the PCell objects. The same PCell object can be used for multiple instances.child_cells={ "ring1" : my_ring1, "ring2" : my_ring2, "spl" : my_splitter, "com" : my_splitter # the same cell is used both for splitting and combining }
The connectivity between the instances of the child cells is set by a list of tuples containing pairs of instance terms/port names. This list
links
is of the forminstname:portname
links=[ ("spl:arm1", "arm1:in1"), ("arm1:out1", "com:arm1"), ("spl:arm2", "arm2:in1"), ("arm2:out1", "com:arm2") ]
All the unused terms of the instances are connected to outside terms. You can override the default external term names using the
external_port_names
property. There you can specify the individual names of the external terms. If no name is specified, the default pattern of ‘instname_termname’ will be used.external_port_names={ "spl:in1" : "input", "com:out1" : "output" }
The PCell will place the waveguides and connect them logically in the netlist, but it is up to the user to verify whether the physical location of the connected ports matches.
In the layout, the placement is specified manually using the
child_transformations
property, which defines a transformation for each instance. If no transformation if supplied for an instance, no transformation will be applied. It is also possible to supply a coordinate (Coord2) or tuple, which will be interpreted as a position for placement.child_transformations={"arm1": (50, -50), "arm2": (50,50), "com": i3.HMirror(0.0)+i3.Translation((100,0))}
Child cells that are logically connected but where the ports are not physically connected (e.g. by wrong placement), will be connected with visual flylines.
You can subclass this PCell in order to implement your own additional functionality, or define subcircuits that define their own child cells and child transformations. Warning: do not refer to self.child_cells from within an overridden _default_child_transformations - rather refer to the child cell directly (like self.my_child_cell).
Parameters: child_cells: optional
dict to create the instances of the child cells. Format is {‘inst_name1’: PCell}
links: list and List with type restriction, allowed types: [<class ‘_abcoll.Sequence’>], optional
list of tuples connecting the instances. Format is [(‘inst1:term1’,’inst2:term2’), …]
external_port_names: optional
Map of the free instance terms/ports to the names of external terms/ports. Format is a dict {‘inst:term’ : ‘new_term_name’}.If a term/port is not listed, the format instname_portname will be used
cell_instances: _PCellInstanceDict, optional
name: optional
The unique name of the pcell
Views
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Layout
¶ Parameters: flyline_layer: optional
layer to draw flylines of physically unconnected links
flyline_width: float and number > 0, optional
line width of the flylines
view_name: str, optional
The name of the view
child_transformations: optional
dictionary with the transformation of each child instance.
netlist_view: NetlistView, optional
Netlist view in the same cell on which this Layout is based. Normally no need to manually override.
grids_per_unit: locked
Number of grid cells per design unit
units_per_grid: locked
Ratio of grid cell and design unit
grid: float and number > 0, locked
design grid. Extracted by default from TECH.METRICS.GRID
unit: float and number > 0, locked
design unit. Extracted by default from TECH.METRICS.UNIT
Examples
""" Here we connect together 2 splitters and two rings to form a Ring-loaded Mach-Zehnder. We use the splitter twice (as splitter and combiner) but use two different rings. We calculate the transformations of the rings in such a way that the attach correctly to the splitter and combiner """ from technologies import silicon_photonics from ipkiss3 import all as i3 from picazzo3.filters.ring import RingRect180DropFilter, RingRectNotchFilter from picazzo3.wg.splitters import WgY180Splitter from picazzo3.routing.place_route import PlaceAndConnect from ipkiss.geometry.vector import vector_match_transform # both rings have the same size ring1 = RingRectNotchFilter() ring1_layout = ring1.Layout() ring2 = RingRect180DropFilter() ring2_layout = ring2.Layout() splitter = WgY180Splitter() splitter_layout = splitter.Layout() pr = PlaceAndConnect(child_cells={"spl": splitter, "com": splitter, "arm1": ring1, "arm2": ring2}, links=[("spl:arm1", "arm1:in"), ("arm1:out", "com:arm1"), ("spl:arm2", "arm2:in1"), ("arm2:out1", "com:arm2")] ) # manually calculate the transformations needed to attach the ports together t_ring1 = vector_match_transform(ring1_layout.ports["in"], splitter_layout.ports['arm1']) t_ring2 = vector_match_transform(ring2_layout.ports["in1"], splitter_layout.ports['arm2']) t_com = vector_match_transform(splitter_layout.ports['arm1'], ring1_layout.ports['out'], mirrored=True) + t_ring1 layout = pr.Layout(child_transformations={"arm1": t_ring1, "arm2": t_ring2, "com": t_com} ) layout.visualize()
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