What is SPI machine?
SPI is solder Paste Inspection, which is between solder paste Printer and SMD. It enables 3D fully inspection of tin paste printing condition on PCB pad. Those unqualified PCB has to be returned to printer for re-printing.
What exactly the SPI do?
SPI machine mainly inspect various fauly tin soldering on each pads,and do a quick locating:
1. Absense of tin paste
2. Quantity of printed tin paste, qualified or not
3. Thickness of pirnted tin paste, qualified or not
4. spread area of printed tin paste, qualified or not
5. Deviation on X/Y coordination
5. Short circuit
6. Unqualified tin paste
etc.
Why SPI so important?
As we know, the most common issue from module failure is faulty soldering on PCB. With SPI,we are able to find out all soldering issues before PCB starts SMD process.
It helped improve production efficiency and greatly decreases failure rate from SMT processing.