place_and_route

ipkiss3.all.place_and_route(insts, specs=None, strict=True)

Function to place and route a series of instances with the help of placement specifications and connectors.

The supported placement specifications and connectors can be found under the i3 namespace (see also Placement and routing reference and Connector reference).

Always be as specific as possible when providing the placement specifications. The placement engine will change the positions of instances that are specified in the specifications list.

For instance, if you have multiple specs without using Place, that tells the placement engine that the location of the full circuit (or at least that one instance) is not important. The instances will still be placed relative to each other as specified, but their position might change when you add more specs. By using Place, you anchor your circuit.

You can chain multiple calls of this function after each other where the output of one call is the input to the insts argument on the next call.

Parameters:

insts: InstanceDict or dict or Layout

In case of a dictionary, it has the form of {inst_name: PCell/Layout view}.

specs: Iterable

List of placement specifications and connector specifications between ports.

strict: bool

If True, any routing error will raise an exception and stop the program flow. If False, any routing error will give a warning and draw a straight line on an error layer. See i3.ConnectLogical for more information.

Returns:

InstanceDict or Layout

• If the input insts argument is an InstanceDict or dict, the function returns an InstanceDict containing the placed instances and any created waveguides.

• If the input insts is a Layout object, the function returns a new Layout instance which includes the original ports and elements, along with the newly placed instances and created waveguides.

See also

ipkiss3.all.Circuit

Convenience PCell that uses place_and_route internally.

ConnectManhattan

ConnectBend

ConnectManhattanTapered

ConnectLogical

Circuit

expose_ports

Examples

import si_fab.all as pdk
import ipkiss3.all as i3
from picazzo3.wg.splitters import WgYSplitter, WgYCombiner

class MyPCell(i3.PCell):
    class Layout(i3.LayoutView):
        def generate(self, layout):
            layout += i3.place_and_route(
                insts={"splitter": WgYSplitter(), "combiner": WgYCombiner()},
                specs=[
                    i3.Place("splitter", (0, 0)),
                    i3.Place("combiner", (30, 20), relative_to="splitter"),
                    i3.ConnectManhattan(
                        "splitter:arm2",
                        "combiner:arm2",
                        control_points=[i3.H(50)],
                        bend_radius=5.0,
                    ),
                    i3.ConnectManhattan(
                        "splitter:arm1", "combiner:arm1", "wg_name", bend_radius=5.0
                    ),
                ],
            )
            layout += i3.expose_ports(
                layout, {"splitter:center": "input", "combiner:center": "output"}
            )
            return layout

pcell = MyPCell()
pcell_lo = pcell.Layout()
pcell_lo.visualize(annotate=True)