SPI

Solder Paste Inspection

LingtechPCB SMT production has deployed automatic SPI machine to check the solder paste printing quality,

to ensure best soldering quality.

SPI, the full name of solder paste inspection, is an SMT inspection device that uses optical principles to calculate the height of the

solder paste printed on the PCB by triangulation. It is the quality inspection of solder printing and the verification and control of the

printing process.

1.The function of SPI:

• Discover the lack of print quality in time.

• SPI can intuitively tell users which solder paste printing effects are good and which ones are not good,

• and give points for which defects belong to.

• SPI detects quality trends by testing a series of solder pastes, and Identify the underlying factors that cause this trend before the

        quality is out of range, For    example, the control parameters of the printing machine, human factors, solder paste change

        factors, etc. Then we can make timely adjustments to control the continued spread of trends.

2.What to be detected:

    Height, volume, area, position misalignment, diffusion, missing, breakage, height deviation (tip)

3.The difference between SPI & AOI:

(1) After the solder paste is printed, before the SMT machine, pass through the solder paste inspection machine (with a laser device that can detect

     the thickness of the solder paste).

(2) Following the placement machine, AOI is component placement inspection (before reflow soldering) and

    solder joint inspection (after reflow soldering).