Introduction to Surface Mount Technology

Surface Mount Technology (SMT) refers to a specific type of electronics assembly where electronic components are attached to the surface of a substrate (typically a printed circuit board).

SMT is a modern alternative to traditional thru-hole technology where components are attached to substrates by leads that passed through holes in the PCB.

Surface Mount components require less space so SMT is helpful in product miniaturization.

SMT Overview
SMT V/S THROUGH HOLE
Basic SMT process flow
Equipments used SMT Assembly
Through Hole Assembly & Soldering
ELECTROSTATIC DISCHARGE
RoHS

1. A Seminar on SURFACE MOUNT TECHNOLOGY & PRINTED CIRCUIT BOARD ASSEMBLY TECHNOLOGICAL ADVANCEMENTS PRESENTED BY: Mr. ABDUL MUNAFF Asst. Professor DEPARTMENT OF ELECTICAL & ELECTRONICS ENGINEERING, SIET, VIJAYAPURA.

2. Surface Mount Technology

3. Surface Mount Device (SMD)

4. ORGANIZATION OF PRESENTATION Objective of this Seminar SMT Overview SMT V/S THROUGH HOLE Basic SMT process flow Equipments used SMT Assembly Through Hole Assembly & Soldering ELECTROSTATIC DISCHARGE RoHS Outcome

5. Objective of this Seminar INSPIRING CREATIVE & INNOVATIVE MINDS KT (Knowledge Transfer) Technology Awareness yh

6. SMT Overview Surface Mount Technology (SMT) refers to a specific type of electronics assembly where electronic components are attached to the surface of a substrate (typically a printed circuit board). SMT is a modern alternative to traditional thru-hole technology where components are attached to substrates by leads that passed through holes in the PCB. Surface Mount components require less space so SMT is helpful in product miniaturization. Miniaturization means – The process of making something very small using Modern Technology

7. Surface Mount Vs Thru Hole Double-Sided Surface Mount Through-hole Technology

8. Basic SMT process flow

9. Load Bare PCB: Basic SMT process flow PCB Surface Mount Pad Surface Mount Pad Through hole Pad 1 Typical PCB insulated substrate copper connections protective covering

10. Solder Paste Print: A stencil printer is used to print solder paste onto PCB. PCB Stencil frame Stencil Squeegee Solder Paste Snap-off The main reason for printing solder paste onto the PCB is to supply solder alloy for the solder joints. Solder Paste

11. Place Surface Mount Components: One or more pick and place or “chip shooter” machines are used to accurately place SMT components onto PCB. SMT Component Lead Pick and Place Machine Nozzle

12. Reflow: A reflow oven heats the PCB to a temperature that melts the solder alloy. Solder Joint Fillet

13. Cleaning: The PCB is cleaned of flux residues if necessary.

14. Equipments used SMT Assembly

15. SOLDER PASTE

16. STENCIL Polyester Mesh Stencil Frame Metal Foil Epoxy Aperture

17. STENCIL

18. SOLDER PASTE PRINTER

19. CHIP SHOOTER/PICK n PLACE MACHINE

20. REFLOW OVEN

21. REFLOW OVEN

22. REFLOW OVEN

23. Why Use Surface Mount Technology? Miniaturization of Products. SMD’s have improved performance over through-hole components due to their smaller size, shorter internal leads and smaller board layouts. SMDs can be more cost effective than traditional through-hole components due to the smaller board size, fewer board layers and fewer holes. Smaller component size: Typical size (1206 - 0.12" × 0.06" ). Faster assembly: Some placement machines are capable of placing more than 1,36,000 components per hour. Types of SMD’s

24. Main disadvantages The manufacturing processes for SMT are much more sophisticated than through-hole, raising the initial cost and time of setting up of production. Manual prototype assembly or component-level repair is more difficult. SMDs cannot be used directly with breadboards.

25. THROUGH HOLE

26. WAVE SOLDERING

27. WAVE SOLDERING

28. ELECTROSTATIC DISCHARGE Electrostatic discharge ( ESD ) is the sudden flow of electricity between two electrically charged objects caused by contact, an electrical short , or dielectric breakdown . The ESD occurs when differently-charged objects are brought close together or when the dielectric between them breaks down, often creating a visible spark .

29. ELECTROSTATIC DISCHARGE

30. Restriction of Hazardous Substances ( RoHS The Restriction of Hazardous Substances Directive 2002/95/EC, ( RoHS ), short for Directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment, was adopted in February 2003 by the European Union. This directive restricts (with exceptions ) the use of six hazardous materials in the manufacture of various types of electronic and electrical equipment. It is closely linked with the Waste Electrical and Electronic Equipment Directive (WEEE), which sets collection, recycling and recovery targets for electrical goods and is part of a legislative initiative to solve the problem of huge amounts of toxic electronic waste .

31. Restriction of Hazardous Substances ( RoHS ) Lead (Pb ): < 1000 ppm Mercury (Hg): < 100 ppm Cadmium (Cd): < 100 ppm Hexavalent Chromium: (Cr 6+ )) < 1000 ppm Polybrominated Biphenyls (PBB): < 1000 ppm Polybrominated Diphenyl Ethers (PBDE): < 1000 ppm Bis (2-Ethylhexyl) phthalate (DEHP): < 1000 ppm Benzyl Butyl Phthalate (BBP): < 1000 ppm Dibutyl Phthalate (DBP): < 1000 ppm Diisobutyl Phthalate (DIBP): < 1000 ppm

32. OUTCOME Identify Surface Mount Devices and Through Hole Devices. Usage of Presentation Tools. Electro Static Discharge (ESD) Handling PCBA’s Information on RoHS

33. Queries Session This is just an introduction to the Surface Mount Technology, It doesn't end here – It’s a beginning. To be continued……

34. Thank you!!!

35. Outcome based Education ASK – Attitude, Skill & Knowledge