1、 Selection of electronic components

The selection of electronic components should fully consider the actual total area needs of SMB, and conventional electronic components should be selected as much as possible. Blindly pursuing small-sized electronic components is not advisable to avoid increasing costs. IC devices should pay attention to pin shape and pin spacing, and QFP with pin spacing less than 0.5mm should be carefully considered. It is better to directly choose BGA packaged devices. In addition, the packaging form, terminal electrode size, PCB solderability, reliability of SMT devices, and temperature tolerance (such as whether they can meet the needs of lead-free soldering) of electronic components should all be considered.


After selecting electronic components, it is necessary to establish a database of electronic components, including relevant information on installation dimensions, pin dimensions, and SMT manufacturers.


2、 Selection of board materials

The substrate should be selected based on the usage conditions and mechanical and electrical equipment characteristics requirements of SMB; Determine the number of copper clad surfaces of the substrate based on the SMB structure (single-sided, double-sided, or multi-layer SMB); Determine the thickness of the substrate board based on the size of SMB and the weight of electronic components per unit total area. The cost of different types of materials varies greatly, and when selecting SMB substrates, consideration should be given to the requirements of electrical equipment characteristics, Tg (glass transition temperature) CTE、 Factors such as flatness, ability to metalize holes, and price.