654 EMBEDDED SYSTEMS
PCB is very large. e small size of electronic components also make manual soldering
very diffi cult. Automated machine soldering is used in such cases.
ere are two diff erent types of components used:
i) rough hole components
ii) Surface mount components
As the name implies, a ‘through hole’ component is inserted from one side of the
PCB and is soldered on the other side. But a surface mount device (SMD) is soldered
on the surface itself. at means that it does not have any part to be inserted to the other
side of the PCB. Obviously, surface mount devices are small and they help to accom-
modate more components in a small area.
18.4 | Testing
Testing is the process by which it is confi rmed that the designed product ...