PCBA production process can be divided into several major processes, SMT chip processing → DIP plug-in processing → PCBA test → finished product assembly.
1, SMT chip processing process is: solder paste mixing → solder paste printing → SPI → mounting → reflow soldering → AOI → rework
Silk paste mixing: the paste from the refrigerator out of the thawing, the use of manual or machine mixing, in order to be suitable for printing and welding.
Paste Printing: Place the paste on the stencil and print the paste onto the PCB pads by squeegee leakage.
SPI: SPI is the solder paste thickness detector, which can detect the solder paste printing and play a role in controlling the effect of solder paste printing.
Placement: The components are placed on the Flyer, and the head of the placement machine accurately places the components on the Flyer on the PCB pads through identification.
Reflow soldering: the PCB board will be mounted over the reflow soldering, after the high temperature inside the role of the paste paste heat into liquid, and finally cooled and solidified to complete the welding.
AOI: AOI that is, automatic optical inspection, through the scanning of the PCB board can be tested on the welding effect, can detect the board is bad.
Return: AOI or manually detected defects for repair.
2, DIP plug-in processing link
DIP plug-in processing process is: plug-in → wave soldering → clipping feet → post-soldering processing → wash board → quality control
Plug-in: plug-in materials for the processing of the pin, inserted in the PCB board
Wave soldering: will be inserted into the board over the wave soldering, the process will be a liquid tin spray to the PCB board, and finally cooled to complete the welding board, and finally cooled to complete the welding.
Cutting: The pins of the soldered board are too long and need to be cut.
Post-soldering: Soldering components by hand using a soldering iron.
Washing board: after wave soldering, the board will be dirty, need to use the washing water and washing tank for cleaning, or use the machine for cleaning.
Quality inspection: check the PCB board, unqualified products need to be reworked, qualified products to enter the next process.
3, PCBA test
PCBA test can be divided into ICT test, FCT test, aging test, vibration test, etc.
PCBA test is a big test, according to different products, different customer requirements, the means of testing is different. ICT test is the welding of the components, the line of the through the situation of the test. The FCT test is to test the input and output parameters of the PCBA board to see if it meets the requirements.
4, the finished product assembly
The test OK PCBA board for the assembly of the shell, and then test, and finally can be shipped.
PCBA production is a ring with a ring, any one part of the problem will have a very big impact on the overall quality, the need for strict control of each process.