SBendFanout

class ipkiss3.all.SBendFanout

Create S-bend-like routes that fanout all the start ports to evenly spaced outputs. To be used with a bundle connector.

The fanout will route to the nearest manhattan angle and works best when:

• The ports are placed perpendicular to this angle

• The ports are oriented towards this angle

Parameters:

end_position: ( Coord2 ), optional, *None allowed*

Target end position of the reference. If None, the fanout is made as compact as possible.

reference: optional, *None allowed*

Port (instance:port identifier or an actual i3.Port) to align the fanout with. If None, the center of the inputs is used as reference.

max_sbend_angle: float, optional

The maximum angle for the S-bends in the fanout. Defaults to 90 degrees to make the fanout as compact as possible. Lower this value for more gradual bends.

See also

ConnectManhattan

ManhattanFanout

ConnectBend

place_and_route

ConnectManhattanBundle

ConnectElectricalBundle

Examples

Use reference and end_position to control the alignment of the fanout:

import si_fab.all as pdk  # noqa: F401
import ipkiss3.all as i3

start_ports = [
    i3.OpticalPort(name=f"start_port_{i}", position=(0.0, -20.0 + 10 * i), angle=0) for i in range(5)
]
end_ports = [
    i3.OpticalPort(name=f"end_port_{i}", position=(200.0, -20.0 + 10 * i), angle=180) for i in range(5)
]

circuit = i3.Circuit(
    specs=[
        i3.ConnectManhattanBundle(
            connections=list(zip(start_ports, end_ports)),
            start_fanout=i3.SBendFanout(),
            end_fanout=i3.SBendFanout(),
        )
    ]
)

lv = circuit.Layout()
lv.visualize()

circuit = i3.Circuit(
    specs=[
        i3.ConnectManhattanBundle(
            connections=list(zip(start_ports, end_ports)),
            start_fanout=i3.SBendFanout(
                # Route the first start port to (25, -50).
                reference=start_ports[0],
                end_position=(25, -50),
            ),
            end_fanout=i3.SBendFanout(
                # Align the fanout with the last end port.
                reference=end_ports[-1]
            ),
        )
    ]
)

lv = circuit.Layout()
lv.visualize()

Use the max_sbend_angle property to control the angle of the S-bends:

import si_fab.all as pdk  # noqa: F401
import ipkiss3.all as i3

start_ports = [
    i3.OpticalPort(name=f"start_port_{i}", position=(0.0, -20.0 + 10 * i), angle=0) for i in range(5)
]
end_ports = [
    i3.OpticalPort(name=f"end_port_{i}", position=(100.0, -20.0 + 10 * i), angle=180) for i in range(5)
]

circuit = i3.Circuit(
    specs=[
        i3.ConnectManhattanBundle(
            connections=list(zip(start_ports, end_ports)),
            start_fanout=i3.SBendFanout(max_sbend_angle=70),
            end_fanout=i3.SBendFanout(max_sbend_angle=25),
        )
    ]
)

lv = circuit.Layout()
lv.visualize()

Use SBendFanout in electrical bundle:

import si_fab.all as pdk  # noqa: F401
import ipkiss3.all as i3

bp = pdk.BondPad()
M1_wire_tpl = pdk.M1WireTemplate().Layout(width=5)

circuit = i3.Circuit(
    insts={
        "pad1": bp,
        "pad2": bp,
        "pad3": bp,
        "pad4": bp,
        "pad5": bp,
        "pad6": bp,
    },
    specs=[
        i3.Place("pad1:m1", (0.0, -100.0)),
        i3.Place("pad2:m1", (0.0, 0.0)),
        i3.Place("pad3:m1", (0.0, 100.0)),
        i3.Place("pad4:m1", (400.0, 400)),
        i3.Place("pad5:m1", (500.0, 400)),
        i3.Place("pad6:m1", (600.0, 400)),
        i3.ConnectElectricalBundle(
            connections=[
                ("pad1:m1", "pad6:m1"),
                ("pad2:m1", "pad5:m1"),
                ("pad3:m1", "pad4:m1"),
            ],
            start_angle=0,
            start_straight=50,
            start_fanout=i3.SBendFanout(),
            end_angle=-90.0,
            end_straight=50,
            end_fanout=i3.SBendFanout(),
            trace_template=M1_wire_tpl,
            pitch=10,
            min_gap=5,
        ),
    ],
)

circuit_lo = circuit.Layout()
circuit_lo.visualize()