What exactly does smt mean?

SMT is an electronic assembly technology that directly pastes and welds surface assembly components (including resistors, capacitors and inductors). ) to the surface of the circuit board, it is the most popular technology and process in the electronic assembly industry to adopt professional automatic assembly equipment such as solder paste printer, mounter and reflow soldering.

The computers, mobile phones, printers, MP4s, digital images and high-tech control systems we use are all produced by SMT equipment, which is the core technology of modern electronic manufacturing.

If you want to succeed and become a professional, you should pay attention: if you are lazy, tired and bored, and are late for class every day, it is useless to go anywhere. To be a first-class technical talent, you must be more dedicated than others! And the only way to be fast is to train more, really, thoroughly!

Extended data:

Features:

1 High assembly density, small volume and light weight of electronic products. The size and weight of the patch component are only about110 of the traditional plug-in. After SMT, the volume of general electronic products is reduced by 40%~60% and the weight is reduced by 60%~80%.

2. High reliability and strong anti-vibration ability. The defect rate of solder joints is low.

3 Good high frequency characteristics. Reduce electromagnetic and radio frequency interference.

4. It is easy to realize automation and improve production efficiency. Reduce the cost by 30%~50%. Save materials, energy, equipment, manpower, time, etc.

Technology:

Print (or distribute)-> mount->； (curing)-> Reflow soldering->; Cleaning-> Detection->; Repair printing: its function is to print solder paste or patch adhesive on the bonding pad of PCB in order to prepare for the welding of components. The equipment used is a printing machine (solder paste printing machine), which is located at the forefront of SMT production line.

1 dispensing: Since most of the circuit boards used now are double-sided patches, in order to prevent the components on the input surface from falling off due to the secondary melting of solder paste, a dispensing machine is installed on the input surface, which drips glue at a fixed position of the PCB, and its main function is to fix the components on the PCB.

The equipment used is a dispensing machine, which is located at the front end of SMT production line or behind the test equipment. Sometimes, due to the requirements of customers, the output surface also needs dispensing, but now many small factories do not use dispensing machines, so if the input surface components are large, they will use manual dispensing.

2. Installation: Its function is to accurately install the surface assembly components to the fixed position of PCB. The equipment used is mounter, which is located behind the printing machine of SMT production line.

3. Curing: Its function is to melt the chip adhesive, so that the surface assembly components and PCB board are firmly bonded together. The equipment used is the curing furnace, which is located behind the mounter in the SMT production line.

Reflow soldering: Its function is to melt the solder paste, so that the surface assembly components and PCB board are firmly bonded together. The equipment used is a reflow oven, which is located behind the mounter in the SMT production line.

5 cleaning: its function is to remove welding residues harmful to human body on the assembled PCB, such as flux. The equipment used is a cleaning machine, and the location can be not fixed, online or offline.

6 Inspection: Its function is to inspect the welding quality and assembly quality of the installed PCB. The equipment used includes magnifying glass, microscope, on-line tester (ICT), flying needle tester, automatic optical inspection (AOI), X-ray inspection system, function tester, etc. This position can be configured in a suitable position on the production line according to the needs of detection.

7 Rework: Its function is to rework the PCB board whose fault has been detected. Tools used include soldering iron, maintenance workstation, etc. Configured at any position of the production line.

References:

Baidu Encyclopedia-Surface Mount Technology