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.