1、 Basic Process Composition of SMT

Screen printing (or glue)>Mounting>(curing)>Reflow soldering>Cleaning>Testing>Repair

2、 SMT production process flow

1. Surface mount technology

① Single sided assembly: (All surface mounted components are on one side of the PCB)

Incoming inspection - solder paste mixing - silk screen solder paste - SMT - reflow soldering ② double-sided assembly; (Surface mount components are located on both sides A and B of the PCB)

Incoming inspection - PCB A-side silk screen solder paste - SMT - A-side reflow soldering - flipping board - PCB B-side silk screen solder paste - SMT - B-side reflow soldering - (cleaning) - inspection - repair

2. Mixing process

① Single sided mixed assembly process: (Both the plug-in and surface mount components are on the A side of the PCB)

Incoming inspection - Solder paste mixing - PCB A-side silk screen printing solder paste - SMT - A-side reflow soldering - PCB A-side plug-in - Wave soldering or immersion soldering (a small number of plug-ins can be manually soldered) - (cleaning) - Inspection - Repair (paste first, insert later)

② Double sided mixing process:

(Surface mount components are on the A side of the PCB, and plugs are on the B side of the PCB)

A、 Incoming inspection - Solder paste mixing - PCB A-side silk screen printing solder paste - SMT - Reflow soldering - PCB B-side plug-in - Wave soldering (a small number of plug-ins can be manually soldered) - (cleaning) - Inspection - Repair

B、 Incoming inspection - PCB A-side silk screen solder paste - SMT - manual soldering inventory of PCB A-side plugs - solder paste - PCB B-side plugs - reflow soldering - (cleaning) - inspection - repair

(Surface mount components are on the A and B sides of the PCB, and plugins are on either or both sides of the PCB)

First, perform reflow soldering of surface mount components on both sides A and B of the double-sided PCB using the double-sided assembly method, and then manually solder the plugs on both sides.