1.2 Type II assembly:

Here the primary side contains both through-hole and surface mount components. The secondary side contains only surface mount components. This kind of mixed assembly is still prevalent primarily due to unavailability/ cost considerations of surface mount components to that of through-hole components. The typical process steps are shown below.

The above classification is given in broad sense and there is no standard industry classification. As can be seen, assembly of mixed component board involves more operations and therefore takes more time for assembly and inspection/ rework.