max_length

Bounding-box length (the long side of a merged region’s axis-aligned bounding box) must be at most value. The dual of max_dim.

Semantics

The extent is a difference of two grid coordinates and is compared exactly against value on the grid.

For each merged region on the rule’s layer, take its axis-aligned bounding box (x0, y0)-(x1, y1) and compute length = max(x1 - x0, y1 - y0). A region whose length exceeds value is a violation.

Commonly paired with min_length to bound a stripe-like feature’s length to a range, as IHP’s NPN transistor emitter-length rules do ([0.90, 0.90], [1.00, 2.50], [1.00, 5.00] for the three emitter variants).

Layers

A single layer, layers[0].

Parameters

None — only value (µm).

Violation markers

One point marker per offending merged region, at its centroid (owned by the tile whose core contains that centroid).

KLayout equivalent

Region#with_bbox_max(value + one grid step, nil): the polygons whose bounding box’s larger side is over value, which is how IHP’s deck reads its metal-filler maxima (MnFil.a2, TMnFil.a1) and LBE.b.

Example

- id: npn13G2.a
  check: max_length
  layers: [EmitG2]
  value: 0.90