PCBA Tech - Analyze the PCBA production process for you

Analyze the PCBA production process for you
PCBA refers to the process of mounting, inserting and soldering bare PCB components. The PCBA production process needs to go through a series of processes to complete the production. Next, the editor will introduce the various processes of PCBA production.

PCBA production process can be divided into several major processes, SMT patch processing-DIP plug-in processing-PCBA testing-finished product assembly.

One, SMT patch processing link

The process of SMT chip processing is: solder paste mixing - solder paste printing - SPI - placement - reflow soldering - AOI - rework

1, solder paste mixing

After the solder paste is taken out of the refrigerator and thawed, it is stirred by hand or machine to suit printing and soldering.

2, solder paste printing

Put the solder paste on the stencil, and use a squeegee to print the solder paste onto the PCB pads.

3, SPI

SPI is the solder paste thickness detector, which can detect the printing condition of the solder paste and play the purpose of controlling the printing effect of the solder paste.

4. Mounting

SMD components are placed on the feeder, and the placement machine head accurately mounts the components on the feeder on the PCB pads through identification.

5. Reflow soldering

The mounted PCB board is reflow soldered, and the paste-like solder paste is heated to liquid through the high temperature inside, and finally cooled and solidified to complete the soldering.

6, AOI

AOI is automatic optical inspection, which can detect the welding effect of PCB board through scanning, and can detect the defects of the board.

7, repair

Rework the defects detected by AOI or manually.

2. DIP plug-in processing link

The process of DIP plug-in processing is: plug-in-wave soldering-cutting feet-post-welding processing-plate washing-quality inspection

1, plug-in

Process the pins of the plug-in materials and insert them on the PCB board

2, wave soldering

The inserted board is subjected to wave soldering. In this process, liquid tin will be sprayed onto the PCB board, and finally cooled to complete the soldering.

3, cut feet

The pins of the soldered board are too long and need to be trimmed.

4, post welding processing

Use an electric soldering iron to manually solder the components.

5, wash the plate

After wave soldering, the board will be dirty, so you need to use washing water and washing tank to clean it, or use a machine to clean it.

6, quality inspection

Inspect the PCB board, the unqualified products need to be repaired, and the qualified products can enter the next process.

Three, 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 and different customer requirements, the test methods used are different. The ICT test is to detect the welding conditions of the components and the on-off conditions of the circuit, while the FCT test is to detect the input and output parameters of the PCBA board to see if it meets the requirements.

Fourth, finished product assembly

The PCBA board with the test OK is assembled on the shell, and then tested, and finally it can be shipped.

PCBA production is one link after another. Any problem in any link will have a very large impact on the overall quality, and strict control of each process is required.