Surface Mount Interconnects (SMIs)

smi diagram 1

Surface mount interconnects (SMIs) is the world’s first fully machine placeable interconnection component. This tech, which are supplied in standard 13 inch (330mm) diameter reels of 1500 circuits, is available with 4 to 22 conductors on a 0.93mm pitch and with 10 to 40 conductors on a 0.50mm pitch.

With this tech we can achieve a level of co-planarity which allows the SMI to be accurately placed by all industry standard “pick & place” machines. The SMIs are assembled directly into solder paste in the same way and during the same process cycle as all other components are placed. The solder joints are made during the reflow process again utilizing industry standard equipment.

SMIs are a low cost product for board to board interconnection. The constructions and materials have been specifically selected to provide the most reliable and cost-effective solution.

Benefits:

Applications:

The SMI technology has been successfully employed in many applications including:

Typical footprint details for the rigid PCB for 0.5mm pitch SMI

All dimensions are millimetres

Specification

Conductor pitch
0.50mm pitch

0.93mm pitch

0.50mm and 0.93mm
10 to 40 conductors (as standard)

4 to 22 conductors (as standard)

Standard size

Conductor length - 15mm

Width-Varies according to number of conductors

Maximum height 1mm

Copper thickness
(exposed finger area)

250 micron ± 10%

Copper thickness (bend area)

70 micron - 125 micron

Co-planarity of exposed fingers

150 micron (total) 0.93mm pitch
100 micron (total) 0.50mm pitch

Insulation thickness

25 micron ± 10%

Dielectric material

Polyimide (standard)

Temperature range

Assembly 150ºC to 250ºC typical SMT flow
Operation -60ºC to +125ºC cyclic, +105ºC continuous

Current rating (per conductor)

0.50mm pitch 1.0A for 10ºC rise above ambient

0.93mm pitch 1.5A for 10ºC rise above ambient

Flexural performance

180º bend + > 100+ cycles 2mm bend radius

Land finish

RoHS standard. Other finishes e.g. tin/lead available upon request

Custom designs available if required

See also