tidy3d.LumpedResistor

class LumpedResistor

Bases: AbstractLumpedResistor, Box

Class representing a rectangular lumped resistor. Lumped resistors are appended to the list of structures in the simulation as Medium2D with the appropriate conductivity given their size and voltage axis.

Parameters:

• attrs (dict = {}) – Dictionary storing arbitrary metadata for a Tidy3D object. This dictionary can be freely used by the user for storing data without affecting the operation of Tidy3D as it is not used internally. Note that, unlike regular Tidy3D fields, attrs are mutable. For example, the following is allowed for setting an attr obj.attrs['foo'] = bar. Also note that Tidy3D` will raise a TypeError if attrs contain objects that can not be serialized. One can check if attrs are serializable by calling obj.json().

• center (Union[tuple[Union[float, autograd.tracer.Box], Union[float, autograd.tracer.Box], Union[float, autograd.tracer.Box]], Box] = (0.0, 0.0, 0.0)) – [units = um]. Center of object in x, y, and z.

• size (Union[tuple[Union[pydantic.v1.types.NonNegativeFloat, autograd.tracer.Box], Union[pydantic.v1.types.NonNegativeFloat, autograd.tracer.Box], Union[pydantic.v1.types.NonNegativeFloat, autograd.tracer.Box]], Box]) – [units = um]. Size in x, y, and z directions.

• name (ConstrainedStrValue) – Unique name for the lumped element.

• num_grid_cells (Optional[PositiveInt] = 3) – Number of mesh grid cells associated with the lumped element along each direction. Used in generating the suggested list of MeshOverrideStructure objects. A value of None will turn off mesh refinement suggestions.

• resistance (PositiveFloat) – Resistance value in ohms.

• voltage_axis (Literal[0, 1, 2]) – Specifies the axis along which the component is oriented and along which the associated voltage drop will occur. Must be in the plane of the element.

Attributes

normal_axis	Normal axis of the lumped element.
to_structure	Converts the LumpedResistor object to a Structure ready to be added to the Simulation
attrs

Methods

to_mesh_overrides()

Creates a suggested MeshOverrideStructure list that could be added to the Simulation.

Inherited Common Usage

voltage_axis

property normal_axis

Normal axis of the lumped element.

to_mesh_overrides()

Creates a suggested MeshOverrideStructure list that could be added to the Simulation.

Note

An important use case is when a LumpedResistor is used with a LumpedPort, where the mesh overrides may be automatically generated depending on num_grid_cells. The port is a flat surface, but when computing the port current, we’ll eventually integrate the magnetic field just above or below this surface. The mesh override needs to ensure that the mesh is fine enough not only in plane, but also in the normal direction. In the normal direction, we’ll make sure there are at least 2 cell layers above and below whose size is the same as the in-plane cell size in the override region. Also, to ensure that the port itself is aligned with a grid boundary in the normal direction, two separate override regions are defined, one above and one below the analytical port region.

property to_structure

Converts the LumpedResistor object to a Structure ready to be added to the Simulation

__hash__()

Hash method.