LMAN models transitions (metal manifolds) between microstrip feeding lines and the body of a Lange coupler. LMAN is intended for use in conjunction with the MLANGE2 (Microstrip Lange Coupler, EM Quasi-Static) element. The layout of the two models match.
|N||Number of Lange coupler fingers||Scalar||4|
|W||Lange coupler finger width||Length||W|
|S||Spacing between Lange coupler fingers||Length||W|
|WL||Width of feeding microstrip line||Length||W|
|WM||Width of manifold side attached to Lange coupler||Length||W|
|Edge||Height of manifold edge (layout parameter only)||Length||0|
N, W, S. These parameters are used to calculate the size of the manifold side attached to the Lange coupler. They are also used in the layout cell to calculate the positions of faces that provide connection to Lange fingers (see the "Topology" section).
Edge. The electrical model does not use this parameter. This parameter is set in Layout View only. To set the Edge, right-click the LMAN shape in the Layout View, choose to display the Cell Options dialog box, then click the Parameters tab. Set the Edge to the desired value.
Parameter N must be even and within range 4≤N≤16.
Parameter WL must be equal to the width of the microstrip line attached to the manifold.
Parameter WM defines the side of the manifold attached to the Lange coupler. WM must be big enough to provide a connection to all fingers attached to the manifold (see the "Topology" section). The minimal value of WM is equal to WMmin = 2[N/4](W+S)+W where  is the integer. If WM<WMmin, then the model sets WM=WMmin and issues a warning.
Capacitances C, Ccoup, and inductance L (see the "Equivalent Circuit" section) are evaluated using Method of Moments. Implementation is based on a static Green's function technique in conjunction with approximation of Green's function in the spectral domain. Polarization and conductive losses are not included.
To decrease the calculation time for schematics that contain several manifolds, cache is implemented for this model. During the first evaluation of schematic capacitances for each manifold, instances are stored in memory cache and saved to the hard drive. Each manifold model in every new schematic/project checks this cache looking for its duplicate. Duplicate manifolds copy the manifold capacitances from memory cache, saving substantial recalculation time.
LMAN assumes that both parts of the manifold have a triangular shape. Setting the Edge parameter to a nonzero value modifies the manifold shape in layout, but has no effect on calculated electrical parameters. The layout cell sets the maximum limit on the value of Edge at WL/2.
This element uses line types to determine its layout. By default, the layout uses the first line type defined in your Layout Process File (LPF). You can change the element to use any of the line types configured in your process:
Select the item in the layout.
Right-click and chooseto display the Cell Options dialog box.
Click the Layout tab and select a Line Type.
Clickto use the new line type in the layout.
See “Cell Options Dialog Box: Layout Tab ” for Cell Options dialog box Layout tab details.
See “The Layout Process File (LPF)” for more information on editing Layout Process Files (LPFs) and to learn about adding or editing line types.
LMAN is intended for use in conjunction with MLANGE2. LMAN provides a layout matching the layout of MLANGE2.
The implementation of this element relies on the involved numerical algorithms. This may lead to an increase in simulation time for schematics that employ many differing instances of LMAN.