smt module

chip_lead_profile(chip)

Build the IPC lead profile for a two-pin SMT chip case size.

The protrusion type selects between the two IPC-7351B fillet tables for rectangular end components: Table 3-5 covers chips “Equal to or Larger than 1608 (0603)” and Table 3-6 those smaller. 1608 is the metric code – imperial 0603 at 1.6 x 0.8 mm – and the boundary is inclusive, so 0603 uses Table 3-5 (BigRectangularLeads). Testing the body length as well as the width keeps the sub-1608 reverse-geometry sizes (0204, 0306, 0505, 0508) in Table 3-6, where their metric codes put them. Rev B gives no explicit rule for reverse geometry, so that part is a judgement call rather than a citation.

Parameters:

chip (SMTChipDef) – the case size definition

Return type:

LeadProfile

Returns:

the lead profile for this case size

class SMTBase(case_name: str, *, side_fillet: float | None = None, height: Toleranced | None = None)

Bases: PackageBodyMixin, LeadProfileMixin, DensityLevelMixin, GridPadShapeGeneratorMixin, GridLayoutInterface, LandpatternGenerator

Parameters:

• case_name (str)

• side_fillet (float | None)

• height (Toleranced | None)

class SMTDecorated(*args, **kwargs)

Bases: SilkscreenOutline, OriginMarkerMixin, ExcessCourtyard, SMTBase

class CathodeAnodeNumbering

Bases: GridLayoutInterface

a: Pad | None = None

c: Pad | None = None

class PolarizedSMT(*args, **kwargs)

Bases: CathodeAnodeNumbering, Pad1Marker, SMTDecorated

class SMT(*args, **kwargs)

Bases: LinearNumbering, SMTDecorated

class O4O2

Bases: SMT