The size of HDI is limited by the capacity of electronic processing production line equipment, therefore, appropriate HDI size should be considered in product system design.

(1) The maximum HDI size that SMT devices can mount comes from the standard size of HDI sheets, most of which are 20 " × 24 ″, i.e. 508mm × 610mm (rail width)

(2) The recommended size is a relatively suitable size for each equipment on the SMT production line, which is conducive to maximizing the production efficiency of each equipment and eliminating equipment bottlenecks.

(3) For small-sized HDI, it should be designed as a combination to improve the production efficiency of the entire production line.

Design Requirements

(1) In general, the maximum size of HDI should be limited to 460mm × Within the range of 610mm.

(2) The recommended size range is (200-250) mm × (250~350) mm, the aspect ratio should be<2.

(3) For dimensions of 125mm × 125mm HDI should be assembled to the appropriate size.

2. HDI appearance

Background Description

SMT production equipment uses guide rails to transport HDI, and cannot transport irregular shaped HDI, especially those with notches in the corners.

Design Requirements

(1) HDI should have a regular square shape and rounded corners.

(2) To ensure the smoothness of the transmission process, irregular shaped HDI should be converted into standard square shapes by splicing, especially the corner notches, which should be filled to avoid jamming during the wave soldering claw transmission process.

(3) Pure SMT boards are allowed to have gaps, but the gap size should be less than one-third of the length of the edge. For those exceeding this requirement, the design process should be supplemented at the same time.

(4) The chamfering design of the golden finger not only requires chamfering on the insertion edge, but also on both sides of the insertion board (1-1.5) × 45 ° chamfer for easy insertion.