20 details in SMT, which one do you know?

details in SMT

SZTech-SMT shares some details about the process of SMT chip processing and production.

1. Generally speaking, the regular temperature of the SMT patch processing workshop is 25±3°C;

2. When printing solder paste, the required materials, and items are: solder paste, scraper, steel plate, wiping paper, cleaning agent, dust-free paper, mixing knife;

3. The main components in solder paste are divided into two categories: tin powder and flux;

4. The solder paste alloy composition is generally Sn/Pb alloy, and Sn accounts for 63%, Pb accounts for 37%;

5. The volume ratio of flux and tin powder particles in solder paste is 1:1, and the ratio of components is about 9:1;

6. The principle of taking solder paste is first in first out;

7. When the solder paste is used in Kaifeng, it must go through two important processes of warming and mixing;

8. The primary role of flux in soldering is to remove oxides, damage the surface tension of molten tin, and prevent re-oxidation.

9. Common manufacturing methods for steel plates are etching, laser, electroforming;

10. The full name of SMT chip processing is the Surface mount (or mounting) technology, which means surface adhesion (or mounting) technology in Chinese

11. ESD is the English abbreviation of “Electrostatic discharge”, which means “electrostatic discharge” in Chinese;

12. When writing the SMT placement machine program, the program includes five types of data, namely: PCB data; Mark data; Feeder data; Nozzle data; Part data;

13. The melting point of lead-free solder Sn/Ag/Cu (96.5/3.0/0.5) is 217°C;

14. The common raw material of SMT stencil is stainless steel;

15. The thickness of the SMT stencil is 0.12-0.15mm; (except for special processes)

16. The relative temperature and humidity of the parts drying box should be less than 10%;

17. Commonly used passive components (Passive Devices) include: resistors, capacitors, point senses (or diodes), etc.; active components (Active Devices) include: transistors, ICs, etc.;

18. In the exclusion number ERB-05604-J81, “4” indicates 4 loops with a resistance value of 56 ohms.

19. The 0603 of the imperial scale represents the length*width of 0.06inch*0.03inch, and the 3216 of the metric scale represents the length*width of 3.2mm*1.6mm;

20. The types of electrostatic charges include separation, conflict, induction, and electrostatic conduction; the impact of electrostatic charges on the SMT chip processing industry is ESD failure, and electrostatic pollution; the three principles of static electricity elimination are electrostatic neutralization, grounding, and shielding.


Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top