|This article does not cite any references or sources. (March 2008)|
The industrial electronics manufacturing process for the electronic assemblies found in many of today's electronic devices, is a multi-step process.
Component and PCB manufacturing
Components such as resistors, capacitors and integrated circuits are generally made by specialized contractors. Integrated circuits are generally made by the process of photolithography. Printed circuit boards (PCBs) are usually manufactured by specialized contractors.
Mounting surface-mount components
- A solder paste is printed where the components need to make a connection with the PCB tracks
- Components are placed using a pick and place machine
- The PCB passes through a reflow oven
The process is repeated twice in order to populate both sides of the PCB.
Mounting through-hole components
In order to increase manufacturing capacity, PCBs are often designed so that they consist of many smaller individual PCBs that will be used in the final product. This PCB cluster is called a panel or multiblock. The large panel is depaneled at some stage in the process.
Cleaning and drying
A completed assembly needs to be cleaned. Various techniques are used depending on what type of solder and flux was used. A cleaned assembly needs to be dried before any power can be applied.
The case-up process consists of one or more of the following:
- Adding a conformal coating or potting
- Final mounting of the depaneled PCB in an enclosure using various methods: screwing etc.°≈°
Electronic assemblies are tested at various process steps using the following methods:
- In-circuit testing of integrated circuits and other components
- Inspection of components and joint quality, using simple visual inspection, X-Ray inspection (usually of invisible joints, e.g. BGA), and/or automated optical inspection
- Final functional test after case-up
- Various other tests for assembly functioning in a range of conditions (temperature, humidity, vibration, strain, etc.)
Sometimes, when only one or two finished devices will be needed, they are put together using one of the more durable electronics prototyping techniques.