PCB Assembly - A Step by Step Guide

PCB Assembly is the process of assembling various components like integrated circuits, capacitors, resistors, connectors, etc. on a Printed Circuit Board (PCB).

1. Application of solder past to the base PCB. For surface mount components via use of a thin, stainless steel stencil & fixture solder paste is applied evenly over the solder pads in the exact locations required on the PCB.
2. Via an automated pick and place operation, the surface mount components are removed from their packaging and moved by a robotic device to the correct location on the PCB and placed into the pre-deposited solder paste.
3. Next, the PCB with paste and applied components is moved to a reflow furnace with various temperature zones which progressively heat the PCB assembly until the reflow temperature of the chosen solder paste is exceeded and subsequently, the temperature’s decreased gradually through subsequent zones of the oven so the solder solidifies, and the until cools.
4. After the reflow process completes, the assembled board is tested and inspected for functionality, this may be via:
   1. Manual visual inspection
   2. Automated Optical Inspection (high-powered cameras set at different angles to view the solder connections and components)
   3. X-Ray inspection
5. Plated through-hole component insertion. After insertion into the correct PCB location these devices are soldered either by manual or wave soldering techniques.
6. Final Inspection is conducted one the soldering process is complete for all surface mount and through-hole components. Usually this is a manual visual inspection under magnification by train operators. Electrical test may be conducted by running power to the PCB assembly and simulating signals to test the electrical characteristics of the design.

Optima Technology is a global provider of PCBs, PCB Assemblies, Cables and System Assemblies located in Lewisberry, PA and New Delhi, India. Since 1995, Optima has specialized in providing local support coupled with cost-effective pricing via offshore manufacturing through our ISO approved facilities. Please reach out to optima@optimatech.net if you’d like to discuss further your PCB or Electronic Assembly needs.